Draft California 2024 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 8 - Santa Ana Region

Water Body Name: Peters Canyon Wash (Orange County)
Water Body ID: CAR8011100020050602204221
Water Body Type: River & Stream
 
DECISION ID
153775
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Benthic Community Effects
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Benthic Community Effects are being considered for placement on the CWA section 303(d) List under sections 3.9 of the Listing Policy. Under section 3.9, additional lines of evidence (LOEs) associating the Benthic Community Effects decision with a water or sediment concentration of pollutants other than benthic-macroinvertebrate bioassessment or habitat assessment LOEs are necessary to place a water body on the 303(d) List for Benthic Community Effects. Six line(s) of evidence evaluating benthic-macroinvertebrate bioassessment data is/are available in the administrative record to assess this indicator. Five of five benthic-macroinvertebrate samples exceed the California Stream Condition Index (CSCI) impairment threshold. Five of the 5 benthic invertebrate samples exceed (fall below) the Southern California IBI threshold for poor community composition.

These data indicate that the waterbody is likely impaired for Benthic Community Effects. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing Benthic Community Effects in this waterbody segment on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Five of five benthic-macroinvertebrate bioassessment samples had CSCI scores below 0.79. The water segment exhibits significant degradation in biological populations and/or communities as compared to reference site(s) using the SoCal IBI. Therefore, this water body is exceeding the water quality threshold for the protection of the WARM beneficial use.
4. Pursuant to section 3.9 of the Listing Policy, the water segment has associated pollutant(s) samples that exceed water quality objectives. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

The California Stream Condition Index is a new scoring tool for bioassessment data that is applicable statewide, accounts for a much wider range of natural variability, and provides equivalent scoring thresholds in all regions of the state. The CSCI has been used in some assessments this reporting cycle and will be used in the future for water quality assessment purposes statewide over the regional indices of biologic integrity (IBIs). If CSCI scores have not be calculated for data and only IBI scores are available, IBI scores will still be used to interpret the data.

CSCI scores representing min and max scores for this site were submitted by OCPW during our comment period. The CSCI scores do not change the listing decision and the IBI LOEs will be retired when the CSCI LOEs are written.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem. Based on the readily available data and information, the weight of evidence provides sufficient justification for placing Benthic Community Effects in this water segment on the CWA section 303(d) List.
 
State Board Review of Regional Board Conclusion and Recommendation: The California Stream Condition Index is a new scoring tool for bioassessment data that is applicable statewide, accounts for a much wider range of natural variability, and provides equivalent scoring thresholds in all regions of the state. The CSCI has been used in some assessments this reporting cycle and will be used in the future for water quality assessment purposes statewide over the regional indices of biologic integrity (IBIs). If CSCI scores have not be calculated for data and only IBI scores are available, IBI scores will still be used to interpret the data.

CSCI scores representing min and max scores for this site were submitted by OCPW during our comment period. The CSCI scores do not change the listing decision and the IBI LOEs will be retired when the CSCI LOEs are written.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 21445
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 43
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Of the 72 samples collected 43 exceeded the Basin Plan's Objective.
Data Reference: Orange County Coast Keeper Coastal Watersheds Project
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan Objective: The ph of inland surface waters shall not be raised above 8.5 pH units or depressed below 6.5 pH units as a result of controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan for the Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at two stations: Peter's Canyon 1 and Peter's Canyon 2. Peters Canyon 1 is Located in Irvine in upper Peter¿s Canyon Channel on Bryan St. between Jamboree Rd. and Culver Dr.
Peter's Canyon 2 is Located In Irvine in lower Peter¿s Canyon Channel on Barranca Pkwy between Jamboree Rd. and Harvard Av.
Temporal Representation: The samples were collected monthly starting on March 9, 2004 through March 29, 2006.
Environmental Conditions:
QAPP Information: The data's quality is deemed acceptable because it was collected under the auspices of a Regional Board staff's approved quality assurance plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238723
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 1 of the 3 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239621
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 2 of the 4 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237515
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCW171 (Peters Canyon Wash Random Olsen Site 171).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237409
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 4 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2016-06-13 and 2019-09-18
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238156
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT01 ( Peter's Canyon Wash at Barranca ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238164
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 5 samples collected by SWAMP Stream Pollution Trends for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-05-26, Hyalella azteca for Survival on 2011-10-05, Hyalella azteca for Survival on 2012-01-18, Hyalella azteca for Survival on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2013-01-11, Hyalella azteca for Survival on 2013-01-11.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801SDCALT ( San Diego Creek at Alton Parkway ).
Temporal Representation: The samples were collected between the dates of 2011-05-26 and 2013-01-11.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238220
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by RWB8 So. CA Stormwater Monitoring Coalition for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia for Survival, Ceriodaphnia dubia for Young/female. The following tests exhibited toxicity: Ceriodaphnia dubia for Young/female on 2014-06-16.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801S02947 ( Peters Canyon Channel Random SMC Site 02947 ).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238154
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus for Growth (wt/surv indiv), Hyalella azteca for Survival, Chironomus dilutus for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30, Chironomus dilutus for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT02 ( Peter's Canyon Wash Below Fwy 5 ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82120
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Five out of the five samples collected had IBI scores below 40. The scores were, fall 2006: 4.29, spring 2007: 1.43, fall 2007: 5.71, spring 2008: 7.15, fall 2008: 2.86.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The IBI is a multi-metric assessment that employs biological metrics that respond to a habitat or water quality impairment. Each of the biological metrics measured at a site are converted to an IBI score then summed. These cumulative scores are then ranked. For the Southern California IBI, sites with scores below 40 are considered to have impaired conditions.
Guideline Reference: A Quantitative Tool for Assessing the Integrity of Southern Coastal California Streams. Environmental Management. Volume 35, number 1 (2005): pp. 1-13
 
Spatial Representation: Samples were collected at station BPF06, Peters Canyon Wash near Barranca Parkway.
Temporal Representation: The samples were collected in the fall 2006, and the spring and fall of 2007 and 2008.
Environmental Conditions:
QAPP Information: The taxonomic analysis followed the guidelines of the Southern California Freshwater and Marine Invertebrate Taxonomic Associations (SAFIT, SCAMIT). All stream bioassessment sample collection and taxonomic analysis follow the Southern California Regional Watershed Monitoring Program Bioassessment Quality Assurance Project Plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82029
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 10
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Ten of the 72 samples exceeded the water quality objective for copper.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82067
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 67
Number of Exceedances: 6
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Six of sixty seven samples exceed the maximum (Instantaneous) concentration for Malathion in freshwater of 100 ng/L.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The maximum (Instantaneous) concentration for Malathion in freshwater is 100 ng/L.
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: Samples were collected at sites: BARSED and BPF06
Temporal Representation: Samples were collected from 2006 to 2009.
Environmental Conditions:
QAPP Information: Data were submitted with the County of Orange Stormwater Program Quality Assurance Management Plan (QAMP) dated January 2010. However, data were collected prior to the development of this QAMP, therefore the quality of these data are unknown.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82042
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 71
Number of Exceedances: 66
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Sixty-six of the 71 samples exceeded the water quality objective for selenium.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for selenium is 5.0 ug/L.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82061
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Thirteen samples were collected to evaluate sediment toxicity. Five of the thirteen samples exhibited significant toxicity. The toxicity tests included survival of Hyallela.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Assessing the Toxicity of Sediment-associated Contaminants with Estuarine and Marine Amphipods. June 1994. EPA 600/R-94/025
 
Spatial Representation: The samples were collected in Peters Canyon Wash.
Temporal Representation: The samples were collected from approximately three times a year from 2006 to 2010.
Environmental Conditions:
QAPP Information: The data collected under the Quality Assurance Management Plan for The Orange County Stormwater Program. The SWAMP measurement quality objectives were followed for toxicity data. The performance of toxicity bioassays and evaluation of reference toxicants were performed using USEPA and Standard Methods.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82062
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample exhibited significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 801SUP065 (Peter's Canyon Wash at Warner).
Temporal Representation: The sample was collected in January 2007.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82054
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 29
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Twenty-nine samples were collected to evaluate water toxicity. Eightof the 29 samples exhibited significant toxicity. The toxicity tests included survival of Fathead, Hyallela, Ceriodaphnia dubia and Purple Urchin development.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected in Peters Canyon Wash.
Temporal Representation: The samples were collected from June 2006 to March 2010.
Environmental Conditions:
QAPP Information: The data collected under the Quality Assurance Management Plan for The Orange County Stormwater Program. The SWAMP measurement quality objectives were followed for toxicity data. The performance of toxicity bioassays and evaluation of reference toxicants were performed using USEPA and Standard Methods.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 314410
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC05379 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.35496805 to 0.35496805.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Inland surface water communities and populations, including vertebrate, invertebrate, and plant species, shall not be degraded as a result of the discharge of waste. Degradation is damage to an aquatic community or population with the result that balanced community no longer exists. The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC05379.
Temporal Representation: Samples were collected from 6/15/2012 to 6/15/2012.
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 314356
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC09091 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.43255342 to 0.43255342.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Inland surface water communities and populations, including vertebrate, invertebrate, and plant species, shall not be degraded as a result of the discharge of waste. Degradation is damage to an aquatic community or population with the result that balanced community no longer exists. The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC09091.
Temporal Representation: Samples were collected from 6/27/2013 to 6/27/2013.
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 314390
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC00899 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.31820179 to 0.31820179.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Inland surface water communities and populations, including vertebrate, invertebrate, and plant species, shall not be degraded as a result of the discharge of waste. Degradation is damage to an aquatic community or population with the result that balanced community no longer exists. The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC00899.
Temporal Representation: Samples were collected from 7/12/2011 to 7/12/2011.
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 314405
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for SMC02947 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.53703555 to 0.53703555.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Inland surface water communities and populations, including vertebrate, invertebrate, and plant species, shall not be degraded as a result of the discharge of waste. Degradation is damage to an aquatic community or population with the result that balanced community no longer exists. The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station SMC02947.
Temporal Representation: Samples were collected from 7/12/2011 to 7/12/2011.
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 314312
 
Pollutant: Benthic-Macroinvertebrate Bioassessments
LOE Subgroup: Population/Community Degradation
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: Benthic macroinvertebrate surveys
Data Used to Assess Water Quality: Water Board staff assessed data for 801S19286 to determine beneficial use support and the results are as follows: 1 of 1 samples exceeded the threshold. CSCI scores were from 0.328013342 to 0.328013342.
Data Reference: California Stream Condition Index (CSCI) Scores for the 2024 Integrated Report for Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Inland surface water communities and populations, including vertebrate, invertebrate, and plant species, shall not be degraded as a result of the discharge of waste. Degradation is damage to an aquatic community or population with the result that balanced community no longer exists. The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The California Stream Condition Index (CSCI) is a biological scoring tool that helps aquatic resource managers translate complex data about benthic macroinvertebrates found living in a stream into an overall measure of stream health. The CSCI score is calculated by comparing the expected condition with actual (observed) results (Rehn, A.C. et al., 2015). CSCI scores range from 0 (highly degraded) to greater than 1 (equivalent to reference). CSCI scoring of biological condition are as follows (per the scientific paper supporting the development of the CSCI scoring tool): greater than or equal to 0.92 = likely intact condition, 0.91 to 0.80 = possibly altered condition, 0.79 to 0.63 = likely altered condition, less than or equal to 0.62 = very likely altered condition. Sites with scores below 0.79 are considered to have exceeded the water quality objective for the aquatic life beneficial use.
Guideline Reference: Bioassessment in complex environments: designing an index for consistent meaning in different settings
 
Spatial Representation: Samples were collected from station 801S19286.
Temporal Representation: Samples were collected from 6/4/2013 to 6/4/2013.
Environmental Conditions:
QAPP Information: Data collected following SWAMP QA protocols.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153775, Benthic Community Effects
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82121
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Bifenthrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
149168
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Indicator Bacteria
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from CWA section 303(d) List under sections 4.2 and 4.3 of the Listing Policy. Under these sections a single line of evidence is necessary to assess listing status.

Two (2) lines of evidence are available in the administrative record to assess this pollutant for the REC-1 beneficial use.

Six (6) of 6 samples exceed the 6-week E. coli Geomean Objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removal of this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six (6) of 6 samples exceed the 6-week E. coli Geomean Objective and and this does exceed the allowable frequency in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

In accordance with section 6.1.5.3 of the Listing Policy, data should be representative of the critical timing that the pollutant is expected to impact the waterbody. Indicator bacteria (total coliform, fecal coliform, E. coli, enterococci) populations may fluctuate substantially on a daily, seasonal, or yearly basis. Lacking constant inputs, they do not persist in the environment for a long period and effects are of relatively short duration. As a result, the historic levels of indicator bacteria in the waterbody may be a poor indicator of current risks to human health, particularly when more recent data are available to sufficiently assess the water quality standard. Additionally, water quality conditions in waterbodies may change as a result of management actions that have been implemented to address bacteria. Unrepresentative data may result in incorrectly placing or not placing a water body segment on the list, which could result in the unnecessary expenditure of public resources or missing a human health problem. Historic lines of evidence for data collected prior to 2010 were evaluated pursuant to these considerations and were not used to assess water quality standards attainment because they do not meet the temporal representation requirements of section 6.1.5.3 of the Listing Policy.

These historical lines of evidence are: 2 LOEs for Total Coliform (82052, 82051), 2 LOEs for Fecal Coliform (82056, 82057), 2 LOEs for Enterococcus (82047, 82048), 1 LOE for E. coli (21468) and will be retired.

For E.coli data, Listing Policy sections 3.3 and 4.3 instructs to use the binomial distribution table in sections 3.2 and 4.2, as applicable. To use the binomial table that uses a four percent exceedance frequency, the data must be collected from coastal beaches or inland surface waters from April 1 through October 31 only, and where collected from inland waters from April 1 through October 31 only, bacterial measurements must be indicative of human fecal matter, and there is substantial human contact in the waterbody.

USEPA 2012 Final Approval Decision Details:

The November 12, 2010 USEPA partial approval letter and the October 11, 2011 final approval letter both from Alexis Strauss, USEPA Region 9, to Tom Howard, SWRCB, concluded the following:

USEPA added Peters Canyon Channel to the list of water quality limited segments requiring a TMDL for indicator bacteria. This water body is designated as a Water Contact Recreation (REC1) water body either explicitly or implicitly as tributaries to other designated segments (RWQCB Santa Ana Region, 2008, Table 3-1, pp.3-23 - 3-35).

The Santa Ana Basin Plan has the following water quality objective for fecal coliform to protect REC1 beneficial use:

Fecal coliform: log mean less than 200 organisms/100 mL based on five or more samples/30 day period, and not more than 10% of the samples exceed 400 organisms/100 mL for any 30-day period. (RWQCB Santa Ana Region, 2008, pp.4-9)

Recent monitoring data collected in this water body measures Escherichia coli (E. coli) indicator bacteria. E. coli is one species within the broader category of fecal coliform bacteria and monitoring data for E. coli can be used to evaluate whether the fecal coliform objective is being met in the subject water body.

In addition, USEPA has recommended that California use USEPA's Ambient Water Quality Criteria for Bacteria (1986) when there is no adopted E. coli standard. Specifically, USEPA recommends that for REC1 beneficial use the following criteria be used:

Steady state geometric mean indicator density - 126 indicator densities/100ml Designated beach area (upper 75% confidence limit) - 235 indicator densities/100ml (EPA, 1986, Table 4, pp.15)

USEPA compared the E. coli data for this water body to the Basin Plan's fecal coliform objective, as well as to USEPA's recommended E. coli criteria and the results were:

1. Forty of the 66 samples taken exceeded the USEPA E. coli criteria (235 organisms/100ml).
2. Thirty-seven of the 66 samples taken exceeded the Basin Plan objective for fecal coliform (400 organisms/100ml).

For this water body segment, sufficient exceedances of the fecal coliform objective and the USEPA recommended criteria exist to merit listings per the 10% exceedance threshold for conventional pollutants expressed in Table 3.2 of the State Listing Policy.

For historical clarification, the Regional and State Water Board detailed decision recommendations made prior to USEPA's final decision are presented in their respective recommendation fields in this decision.

Note: All lines of evidence (LOEs) previously made by the Regional Boards have been revised where necessary in accordance with USEPA's final decision.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation: USEPA 2012 Final Approval Decision Details:

The November 12, 2010 USEPA partial approval letter and the October 11, 2011 final approval letter both from Alexis Strauss, USEPA Region 9, to Tom Howard, SWRCB, concluded the following:

USEPA added Peters Canyon Channel to the list of water quality limited segments requiring a TMDL for indicator bacteria. This water body is designated as a Water Contact Recreation (REC1) water body either explicitly or implicitly as tributaries to other designated segments (RWQCB Santa Ana Region, 2008, Table 3-1, pp.3-23 - 3-35).

The Santa Ana Basin Plan has the following water quality objective for fecal coliform to protect REC1 beneficial use:

Fecal coliform: log mean less than 200 organisms/100 mL based on five or more samples/30 day period, and not more than 10% of the samples exceed 400 organisms/100 mL for any 30-day period. (RWQCB Santa Ana Region, 2008, pp.4-9)

Recent monitoring data collected in this water body measures Escherichia coli (E. coli) indicator bacteria. E. coli is one species within the broader category of fecal coliform bacteria and monitoring data for E. coli can be used to evaluate whether the fecal coliform objective is being met in the subject water body.

In addition, USEPA has recommended that California use USEPA's Ambient Water Quality Criteria for Bacteria (1986) when there is no adopted E. coli standard. Specifically, USEPA recommends that for REC1 beneficial use the following criteria be used:

Steady state geometric mean indicator density - 126 indicator densities/100ml Designated beach area (upper 75% confidence limit) - 235 indicator densities/100ml (EPA, 1986, Table 4, pp.15)

USEPA compared the E. coli data for this water body to the Basin Plan's fecal coliform objective, as well as to USEPA's recommended E. coli criteria and the results were:

1. Forty of the 66 samples taken exceeded the USEPA E. coli criteria (235 organisms/100ml).
2. Thirty-seven of the 66 samples taken exceeded the Basin Plan objective for fecal coliform (400 organisms/100ml).

For this water body segment, sufficient exceedances of the fecal coliform objective and the USEPA recommended criteria exist to merit listings per the 10% exceedance threshold for conventional pollutants expressed in Table 3.2 of the State Listing Policy.

For historical clarification, the Regional and State Water Board detailed decision recommendations made prior to USEPA's final decision are presented in their respective recommendation fields in this decision.

Note: All lines of evidence (LOEs) previously made by the Regional Boards have been revised where necessary in accordance with USEPA's final decision.
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 149168, Indicator Bacteria
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 300965
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: STV
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 2 of the 8 samples exceeded the Statistical Threshold Value (STV) water quality threshold for E. coli. The STV is based on a 10% exceedance rate that is calculated monthly.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial use where the salinity is less than 1 parts per thousand 95 percent or more of the time applies a statistical threshold value to E. coli of 320 cfu/100 mL, not to be exceeded by more than 10 percent of samples within a calendar month (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the days of 2016-06-13 and 2020-08-20 .
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
Line of Evidence (LOE) for Decision ID 149168, Indicator Bacteria
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 301016
 
Pollutant: Escherichia coli (E. coli)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: GeoMean
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 6
Number of Exceedances: 6
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 6 of the 6 samples exceeded the geomean water quality threshold for E. coli. This is a six week rolling geomean that is calculated weekly.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The bacteria water quality objective to protect the REC-1 beneficial use for waters where the salinity is equal to or less than 1 part per thousand 95 percent or more of the time applies a rolling six-week geometric mean of E. coli, not to exceed 100 cfu/100 mL (ISWEBE 2018).
Objective/Criterion Reference: Inland Surface Waters, Enclosed Bays, and Estuaries Plan. Part 1: Trash Provisions; Part 2: Tribal Subsistence Beneficial Uses and Mercury Provisions; Part 3: Bacteria Provisions and Variance Policy
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site(s), station(s): P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the days of 2016-06-13 and 2020-08-20 .
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
 
DECISION ID
132712
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Toxicity
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

Nine lines of evidence are available in the administrative record to assess pollutant. 13 of the 21 sediment samples exceed the WARM Toxicity guideline. Nine of the 32 water samples exceed the WARM Toxicity guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 13 of the 21 sediment samples exceed the WARM Toxicity guideline. Nine of the 32 water samples exceed the WARM Toxicity guideline. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238232
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia for Survival, Ceriodaphnia dubia for Young/female.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801XXX305 ( Peters Canyon Wash Random Olsen Site 305 ).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238220
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by RWB8 So. CA Stormwater Monitoring Coalition for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia for Survival, Ceriodaphnia dubia for Young/female. The following tests exhibited toxicity: Ceriodaphnia dubia for Young/female on 2014-06-16.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801S02947 ( Peters Canyon Channel Random SMC Site 02947 ).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238154
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus for Growth (wt/surv indiv), Hyalella azteca for Survival, Chironomus dilutus for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30, Chironomus dilutus for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT02 ( Peter's Canyon Wash Below Fwy 5 ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238230
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 0 of the 1 samples collected by RWB8 So. CA Stormwater Monitoring Coalition for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Ceriodaphnia dubia for Survival, Ceriodaphnia dubia for Young/female.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801S19286 ( Peters Canyon Wash Random SMC Site 19286 ).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238156
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT01 ( Peter's Canyon Wash at Barranca ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238164
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 5 samples collected by SWAMP Stream Pollution Trends for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-05-26, Hyalella azteca for Survival on 2011-10-05, Hyalella azteca for Survival on 2012-01-18, Hyalella azteca for Survival on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2013-01-11, Hyalella azteca for Survival on 2013-01-11.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801SDCALT ( San Diego Creek at Alton Parkway ).
Temporal Representation: The samples were collected between the dates of 2011-05-26 and 2013-01-11.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82054
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 29
Number of Exceedances: 8
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Twenty-nine samples were collected to evaluate water toxicity. Eightof the 29 samples exhibited significant toxicity. The toxicity tests included survival of Fathead, Hyallela, Ceriodaphnia dubia and Purple Urchin development.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected in Peters Canyon Wash.
Temporal Representation: The samples were collected from June 2006 to March 2010.
Environmental Conditions:
QAPP Information: The data collected under the Quality Assurance Management Plan for The Orange County Stormwater Program. The SWAMP measurement quality objectives were followed for toxicity data. The performance of toxicity bioassays and evaluation of reference toxicants were performed using USEPA and Standard Methods.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82061
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Thirteen samples were collected to evaluate sediment toxicity. Five of the thirteen samples exhibited significant toxicity. The toxicity tests included survival of Hyallela.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Assessing the Toxicity of Sediment-associated Contaminants with Estuarine and Marine Amphipods. June 1994. EPA 600/R-94/025
 
Spatial Representation: The samples were collected in Peters Canyon Wash.
Temporal Representation: The samples were collected from approximately three times a year from 2006 to 2010.
Environmental Conditions:
QAPP Information: The data collected under the Quality Assurance Management Plan for The Orange County Stormwater Program. The SWAMP measurement quality objectives were followed for toxicity data. The performance of toxicity bioassays and evaluation of reference toxicants were performed using USEPA and Standard Methods.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132712, Toxicity
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82062
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample exhibited significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 801SUP065 (Peter's Canyon Wash at Warner).
Temporal Representation: The sample was collected in January 2007.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
 
DECISION ID
132708
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: pH
Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal from the CWA section 303(d) List under section 4.2 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status.

12 lines of evidence are available in the administrative record to assess this pollutant. 53 of the 203 samples exceed the WARM pH objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 53 of the 203 samples exceed the WARM pH objective and this exceeds the allowable frequency listed in Table 4.2 of the Listing Policy.
4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237265
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCWT02 (Peter's Canyon Wash Below Fwy 5).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237515
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCW171 (Peters Canyon Wash Random Olsen Site 171).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237192
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana Region Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for pH.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: BARSED (Peters Canyon Wash @ Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2019-02-04 and 2020-05-05
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237506
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801XXX305 (Peters Canyon Wash Random Olsen Site 305).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2014-06-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237505
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCWT01 (Peter's Canyon Wash at Barranca).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237613
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82041
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 87
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Numeric data generated from 87 minimums and maximums of pH data had 2 exceedences.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of all inland surface waters shall not be depressed below 6.5 or raised above 8.5 as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the BARSED and BPF06 stations.
Temporal Representation: Samples were collected approximately twice a month from July 2006 to June 2009.
Environmental Conditions:
QAPP Information: NPDES quality assurance.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 21445
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 43
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Of the 72 samples collected 43 exceeded the Basin Plan's Objective.
Data Reference: Orange County Coast Keeper Coastal Watersheds Project
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan Objective: The ph of inland surface waters shall not be raised above 8.5 pH units or depressed below 6.5 pH units as a result of controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan for the Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at two stations: Peter's Canyon 1 and Peter's Canyon 2. Peters Canyon 1 is Located in Irvine in upper Peter¿s Canyon Channel on Bryan St. between Jamboree Rd. and Culver Dr.
Peter's Canyon 2 is Located In Irvine in lower Peter¿s Canyon Channel on Barranca Pkwy between Jamboree Rd. and Harvard Av.
Temporal Representation: The samples were collected monthly starting on March 9, 2004 through March 29, 2006.
Environmental Conditions:
QAPP Information: The data's quality is deemed acceptable because it was collected under the auspices of a Regional Board staff's approved quality assurance plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237609
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801SARPCW (Peter's Canyon Wash).
Temporal Representation: The samples were collected between the dates of 2014-05-13 and 2014-05-13
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237409
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 4 of 12 samples exceeded the water quality threshold for pH.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2016-06-13 and 2019-09-18
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237324
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed OCPW Santa Ana Region TMDL Programs data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 1 of 13 samples exceeded the water quality threshold for pH.
Data Reference: WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: BARSED (Peters Canyon Wash @ Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2016-03-30 and 2020-04-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132708, pH
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237396
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for pH.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The pH of inland surface waters shall not be raised above 8.5 or depressed below 6.5 as a result of controllable water quality factors (The Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
149253
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)(2018)
Revision Status Revised
Sources: See TMDL documentation
TMDL Name: Newport Bay Watershed Organochlorine Compounds TMDL
TMDL Project Code: 161
Date TMDL Approved by USEPA: 11/12/2013
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.5 of the Listing Policy. Under section 4.5 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Six lines of evidence are available in the administrative record to assess this pollutant.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Three out of 14 tissue samples exceed the COMM DDT guideline and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. The Newport Bay Watershed Organochlorine Compounds TMDL was approved by USEPA on 11/12/2013.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 149253, DDT (Dichlorodiphenyltrichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238461
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD). Data were collected for 2 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite, 1 composite(s) of Freshwater Clam each composed of 85 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total DDT in shellfish tissue is 23 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 149253, DDT (Dichlorodiphenyltrichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239009
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDT (Dichlorodiphenyltrichloroethane) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for the sum of DDT is the probable effect concentration (PEC) of 62.9 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 149253, DDT (Dichlorodiphenyltrichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82053
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT, Total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for total DDTs is 572 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 149253, DDT (Dichlorodiphenyltrichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 2986
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 14
Number of Exceedances: 3
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Three out of 14 samples exceeded the guideline. A total of 13 whole fish composite samples of red shiner and one whole fish composite of flathead minnow were collected. Red shiner samples were collected in 1992-2002. Flathead minnow sample was collected in 2001. The guideline was exceeded in 1992-93 and 1998 samples of red shiner (TSMP, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Santa Ana River Basin RWQCB Basin Plan: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 1000 ng/g [NAS Guideline (whole fish)] (NAS, 1972).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station located upstream from Irvine Center Parkway Bridge.
Temporal Representation: Samples were collected annually from 1992-2002.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 and 1994-95 Data Reports.

Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 1996-2000. Department of Fish and Game.

Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 2001-2002. Department of Fish and Game.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 149253, DDT (Dichlorodiphenyltrichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82035
 
Pollutant: DDT (Dichlorodiphenyltrichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDT.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDT is 62.9 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 149253, DDT (Dichlorodiphenyltrichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239517
 
Pollutant: Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Total DDT (sum of 4,4'- and 2,4'- isomers of DDT, DDE, and DDD) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for total DDTs is the probable effect concentration (PEC) of 572 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132710
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Selenium
Final Listing Decision: Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: Natural Sources
TMDL Name: TMDLs for Selenium in Freshwater, Newport Bay Watershed
TMDL Project Code: 162
Date TMDL Approved by USEPA: 06/20/2019
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for removal on the CWA section 303(d) List under sections 2.2 and 4.1 of the Listing Policy. Under 4.1 of the Policy, a minimum of one line of evidence is needed to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the CWA section 303(d) List. There is sufficient justification to place it in the Being Addressed portion of the CWA 303(d) List because a TMDL has been completed and approved by RWQCB and USEPA, and is expected to result in attainment of the standard.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 66 of 71 samples exceeded the WARM Selenium criterion and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy.
4. The TMDLs for Selenium in Freshwater, Newport Bay Watershed was approved by USEPA on 06/20/2019.
5. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be removed from the section 303(d) list because applicable water quality standards for the pollutant are being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132710, Selenium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82042
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 71
Number of Exceedances: 66
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Sixty-six of the 71 samples exceeded the water quality objective for selenium.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for selenium is 5.0 ug/L.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132710, Selenium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237709
 
Pollutant: Selenium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Selenium.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The selenium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132717
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Alkalinity as CaCO3
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132717, Alkalinity as CaCO3
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235004
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 801XXX305 (Peters Canyon Wash Random Olsen Site 305).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2014-06-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132717, Alkalinity as CaCO3
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235045
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCW171 (Peters Canyon Wash Random Olsen Site 171).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132717, Alkalinity as CaCO3
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235001
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132717, Alkalinity as CaCO3
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235030
 
Pollutant: Alkalinity as CaCO3
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Alkalinity as CaCO3.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The USEPA recommended alkalinity criterion continuous concentration (CCC) for the protection of aquatic life in freshwater is a minimum value of 20,000 ug/L (4-day average).
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Current as of 08/03/2016.
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
150598
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Ammonia
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Five lines of evidence are available in the administrative record to assess this pollutant. One of the 69 samples exceed the WARM Unionized Ammonia objective and Two of the 66 samples exceed the WARM Unionized Ammonia objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One of the 69 samples exceed the WARM Unionized Ammonia objective and Two of the 66 samples exceed the WARM Unionized Ammonia objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 150598, Ammonia
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82038
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 69
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: One of 69 averaged samples exceed the water quality objective. One detectable sample at 0.19 mg/L did not have corresponding temperature and pH data and was not counted.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The Santa Ana Basin Plan 4-day chronic objective for unionized ammonia and corresponding total ammonia in waters supporting warm freshwater aquatic life is determined by an equation dependent on pH and temperature.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected at stations BPF06 and BARSED which are both at Barranca Parkway.
Temporal Representation: Samples were collected from July 2006 through June 2009.
Environmental Conditions:
QAPP Information: A signed QAPP was included with the stated goal of ensuring the consistent collection of accurate water quality information that will used to satisfy the objectives of the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 150598, Ammonia
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235295
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 1 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCW171 (Peters Canyon Wash Random Olsen Site 171).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 150598, Ammonia
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235271
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801XXX305 (Peters Canyon Wash Random Olsen Site 305).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2014-06-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 150598, Ammonia
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 8515
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 66
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Of the 66 samples collected, two exceeded the Basin Plan's objective. One of the exceedances occurred in Peter's Canyon at station pc1 and the other occurred at station pc2
Data Reference: Orange County Coast Keeper Coastal Watersheds Project
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan Objective: The objective varies according to the temperature of the water being sampled; the objective ranged during the sampling period as follows: 0.10 mg/l - 0.24 mg/l
Objective/Criterion Reference: Water Quality Control Plan for the Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at two stations in the Peter's Canyon Channel: pc1 and pc2
Temporal Representation: The samples were taken monthly starting with 3/9/2004 through 3/29/2006
Environmental Conditions:
QAPP Information: The data's quality is deemed acceptable because it was collected under the auspices of a Regional Board staff's approved quality assurance plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 150598, Ammonia
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235357
 
Pollutant: Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Ammonia as N.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Total Ammonia criterion continuous concentration (expressed as a 30-day average) to protect aquatic life in freshwater is Temperature and pH dependent, and was calculated according to the formula listed in the Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013 document.
Objective/Criterion Reference: Aquatic Life Ambient Water Quality Criteria for Ammonia - Freshwater 2013
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132691
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Arsenic
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 56 samples exceed the beneficial use criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 56 samples exceed the beneficial use criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132691, Arsenic
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235484
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Arsenic.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved arsenic criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is 150 ug/L. The conversion factor used to convert the total fraction criterion for arsenic to dissolved fraction criterion is 1. Therefore all data was considered to be representative of the dissolved fraction. (California Toxics Rule, 2000)
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132691, Arsenic
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238698
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Arsenic .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for arsenic is the probable effect concentration (PEC) of 33 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132691, Arsenic
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82116
 
Pollutant: Arsenic
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 55
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the samples exceeded the water quality objective for arsenic.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The CTR for arsenic is 150 ug/L.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
 
DECISION ID
132692
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Cadmium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 73 samples exceed the WARM Cadmium criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 73 samples exceed the beneficial use criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.

There is also one sediment line of evidence available in the administrative record to assess this pollutant. However, insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132692, Cadmium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82122
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the 72 samples exceeded the water quality objective for cadmium.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132692, Cadmium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238833
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cadmium .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for cadmium is the probable effect concentration (PEC) of 4.98 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132692, Cadmium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235770
 
Pollutant: Cadmium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Cadmium.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved cadmium criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.2 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132693
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Chlordane
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132693, Chlordane
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82123
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Zero of 1 samples collected exceeded the criteria for chlordane concentration (Sum of trans-Chlordane, cis-Chlordane, cis-Nonachlor, trans-Nonachlor, and Oxychlordane).
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The Probable Effect Concentration for Chlordane in freshwater sediments is 17.6 ug/kg(MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected at the following station 801SUP065 (Peter's Canyon Wash @ Warner).
Temporal Representation: The samples were collected on 1/7/2007.
Environmental Conditions:
QAPP Information: The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): Surface Water Ambient Monitoring Program Quality Assurance Program Plan
 
Line of Evidence (LOE) for Decision ID 132693, Chlordane
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238397
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for Chlordane. Data were collected for 2 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite, 1 composite(s) of Freshwater Clam each composed of 85 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for total chlordane in shellfish tissue is 6.0 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132693, Chlordane
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238897
 
Pollutant: Chlordane
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlordane .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for chlordane is the probable effect concentration (PEC) of 17.6 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132694
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Chlorpyrifos
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. However, LOE #82124 summarizes data from sediment pore water and the evaluation guideline is not relevant for this matrix. Therefore, that LOE was removed from and is not included in this decision.

Zero (0) of the 49 water samples exceed the evaluation guideline (Siepmann and Finlayson 2000, with minor corrections to significant figures as described in Beaulaurier et al., 2005) set to protect aquatic life beneficial uses.

Zero of the 6 sediment samples exceed the aquatic life evaluation guideline (Amweg and Weston, 2007).

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of the 49 water samples exceed the evaluation guideline for aquatic life beneficial uses and none of the 6 sediment samples exceeds the aquatic life evaluation guideline. This sample size is sufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132694, Chlorpyrifos
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238899
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Chlorpyrifos .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for chlorpyrifos is the median lethal concentration (LC50) of 1.77 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Amweg and Weston, 2007).
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132694, Chlorpyrifos
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82027
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 49
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of 49 samples exceed the continuous concentration (four day average) for chlorpyrifos in freshwater is 14.0 ng/L. However 13 samples had a reporting limit greater than 14 ng/L rendering them unusable fore assessment purposes.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The Criteria Continuous Concentration (four day average) for chlorpyrifos in freshwater is 14.0 ng/L.
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected at sites: BARSED and BPF06.
Temporal Representation: Samples were collected from 2006 to 2009.
Environmental Conditions:
QAPP Information: Data were submitted with the County of Orange Stormwater Program Quality Assurance Management Plan (QAMP) dated January 2010. The Regional Water Board has determined that equivalent QA/QC documentation exists within the Water Quality Monitoring and Reporting Program for the Orange County MS4 permit and appendix C-11- X of the 2008-09 monitoring report.
QAPP Information Reference(s): Quality Assurance Project Plan for the Orange County Stormwater Program.
 
 
DECISION ID
132721
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Chromium
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero of the 72 samples exceed the WARM Chromium criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 72 samples exceed the WARM Chromium criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132721, Chromium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236103
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Chromium.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is is hardness dependent as described in Table 1 of paragraph (b)(1). The value calculated when using a default hardness of 100 mg/L is 180 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline: The dissolved chromium (III) criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is is hardness dependent as described in Table 1 of paragraph (b)(1). The value calculated when using a default hardness of 100 mg/L is 180 ug/L (California Toxics Rule, 2000).
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132721, Chromium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82028
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the 72 samples exceeded the water quality objective for chromium.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132721, Chromium
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238928
 
Pollutant: Chromium
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Chromium .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for chromium is the probable effect concentration (PEC) of 111 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132718
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Cyfluthrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132718, Cyfluthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236205
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cyfluthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The chronic criterion for cyfluthrin is 0.2 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of cyfluthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cyfluthrin
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132718, Cyfluthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82030
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyfluthrin, total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132718, Cyfluthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238960
 
Pollutant: Cyfluthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cyfluthrin, total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for cyfluthrin is the median lethal concentration (LC50) of 1.1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.1 ug/g is the geometric mean of LC50 values for cyfluthrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132720
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Cyhalothrin, Lambda
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132720, Cyhalothrin, Lambda
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82031
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cyhalothrin, lambda, total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132720, Cyhalothrin, Lambda
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239047
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cyhalothrin, Total lambda- .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for lambda-cyhalothrin is the median lethal concentration (LC50) of 0.44 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.44 ug/g is the geometric mean of LC50 values for lambda-cyhalothrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132720, Cyhalothrin, Lambda
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236235
 
Pollutant: Cyhalothrin, Lambda
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Lambda-cyhalothrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The chronic criterion for lambda-cyhalothrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of lambda-cyhalothrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Lambda-cyhalothrin
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132716
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Cypermethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132716, Cypermethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236331
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Cypermethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The chronic criterion for cypermethrin is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of cypermethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Cypermethrin
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132716, Cypermethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239061
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Cypermethrin, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al., (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132716, Cypermethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82032
 
Pollutant: Cypermethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Cypermethrin, total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for cypermethrin is the median lethal concentration (LC50) of 0.3 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.3 ug/g is the geometric mean of LC50 values for cypermethrin from Maund et al. (2002).
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
149254
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 149254, DDD (Dichlorodiphenyldichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239065
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDD (Dichlorodiphenyldichloroethane) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for the sum of DDD is the probable effect concentration (PEC) of 28 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 149254, DDD (Dichlorodiphenyldichloroethane)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82033
 
Pollutant: DDD (Dichlorodiphenyldichloroethane)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDD.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDD is 28.0 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
149255
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 149255, DDE (Dichlorodiphenyldichloroethylene)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82034
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for DDE.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for sum of DDE is 31.3 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 149255, DDE (Dichlorodiphenyldichloroethylene)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239072
 
Pollutant: DDE (Dichlorodiphenyldichloroethylene)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for DDE (Dichlorodiphenyldichloroethylene) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for the sum of DDE is the probable effect concentration (PEC) of 31.3 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132719
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Deltamethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132719, Deltamethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236386
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Deltamethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the USEPA Aquatic Life Benchmark of 0.000026 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132719, Deltamethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239011
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Deltamethrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132719, Deltamethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82036
 
Pollutant: Deltamethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Deltamethrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for deltamethrin is the median lethal concentration (LC50) of 0.79 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.79 ug/g is the geometric mean of LC50 values for deltamethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
132696
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Diazinon
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under sections 3.1 and 3.6 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status. Under section 3.6, two lines of evidence are needed to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant.

One (1) of the 67 water samples exceed the evaluation guideline.

None of the 7 sediment samples exceed the evaluation guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. One (1) of the 67 water samples exceed the evaluation guideline and none of the 7 sediment samples exceeds the evaluation guideline.
This sample size is sufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.

4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132696, Diazinon
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239022
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Diazinon .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for diazinon is the median lethal concentration (LC50) of 11 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 11 ug/g is the geometric mean of LC50 values for diazinon from Ding et al., (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132696, Diazinon
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82043
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: There is no diazinon evaluation guideline specific to "sediment, interstitial water" (pore water). The following evaluation guideline was used to evaluate an exceedance in water quality standards: the freshwater chronic value for diazinon is 0.1 ug/L, expressed as a continuous concentration (Finlayson, 2004). 
Guideline Reference: Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132696, Diazinon
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82044
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 67
Number of Exceedances: 1
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: One of 67 samples exceeded the continuous concentration for Diazinon criteria of 50.0 ng/L.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: CDFG Hazard Assessment criteria for the protection of Aquatic life is as follows: 50.0 ng/L Continuous Concentration for diazinon in freshwater. (Siepman & Finlayson, 2000).
Guideline Reference: Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
 
Spatial Representation: Samples were collected at sites: BARSED and BPF06
Temporal Representation: Samples were collected from 2006 through 2009.
Environmental Conditions:
QAPP Information: Data were submitted with the County of Orange Stormwater Program Quality Assurance Management Plan (QAMP) dated January 2010. However, data were collected prior to the development of this QAMP, therefore the quality of these data are unknown.
QAPP Information Reference(s):
 
 
DECISION ID
132697
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Dieldrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132697, Dieldrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239118
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Dieldrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for dieldrin is the probable effect concentration (PEC) of 61.8 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132697, Dieldrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82045
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Dieldrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for dieldrin is 61.8 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132697, Dieldrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238321
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Waterboard staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality threshold for Dieldrin. Although data was collected for 1 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite), all 1 sample(s) had to be thrown out due to quantitation issues.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for dieldrin in shellfish tissue is 0.49 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2016-06-06 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132698
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Endosulfan
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132698, Endosulfan
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238423
 
Pollutant: Endosulfan
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 1 samples exceeded the water quality threshold for Endosulfan. Data were collected for 1 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endosulfan (l and ll) in shellfish tissue is 20,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2016-06-06 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132699
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Endrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132699, Endrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238300
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 1 samples exceeded the water quality threshold for Endrin. Data were collected for 1 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for endrin in shellfish tissue is 1,000 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; USEPA, 2000)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Guidance for Assessing Chemical Contaminant Data for Use In Fish Advisories Volume 1: Fish Sampling and Analysis
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2016-06-06 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132699, Endrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82046
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Endrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for endrin is 207 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132699, Endrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239140
 
Pollutant: Endrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Endrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for endrin is the probable effect concentration (PEC) of 207 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132723
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Esfenvalerate/Fenvalerate
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132723, Esfenvalerate/Fenvalerate
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82055
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Esfenvalerate/Fenvalerate, total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132723, Esfenvalerate/Fenvalerate
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236355
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Esfenvalerate. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The chronic criterion for esfenvalerate is 0.3 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of esfenvalerate were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Esfenvalerate
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132723, Esfenvalerate/Fenvalerate
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239198
 
Pollutant: Esfenvalerate/Fenvalerate
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Esfenvalerate/Fenvalerate, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for esfenvalerate/fenvalerate is the median lethal concentration (LC50) of 1.5 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1.5 ug/g is the geometric mean of LC50 values for esfenvalerate/fenvalerate (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132722
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Fenpropathrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132722, Fenpropathrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239240
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Fenpropathrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al., ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132722, Fenpropathrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236196
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Fenpropathrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for Fenpropathrin is the USEPA Aquatic Life Benchmark of 0.0015 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132722, Fenpropathrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82058
 
Pollutant: Fenpropathrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Fenpropathrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fenpropathrin is the median lethal concentration (LC50) of 1 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 1 ug/g is the geometric mean of LC50 values for fenpropathrin from Ding et al. ( 2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
132690
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Fipronil Desulfinyl
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132690, Fipronil Desulfinyl
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236230
 
Pollutant: Fipronil Desulfinyl
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Desulfinyl.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil desulfinyl is the USEPA Aquatic Life Benchmark of 0.54 ug/L for a fish (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: 801SARPCW (Peter's Canyon Wash).
Temporal Representation: The samples were collected between the dates of 2014-05-13 and 2014-05-13
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132724
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Fipronil Sulfone
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the zero (0) samples exceed the beneficial use criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of the zero (0) samples exceed the beneficial use criterion and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132724, Fipronil Sulfone
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82064
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The single sample collected was non-detect. It was not used in the assessment because the laboratory data method detection limit was above the guideline and therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfone is the median lethal concentration (LC50) of 0.12 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132724, Fipronil Sulfone
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236232
 
Pollutant: Fipronil Sulfone
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Fipronil Sulfone.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fipronil degradate fipronil sulfone is the USEPA Aquatic Life Benchmark of 0.037 ug/L for an invertebrate (chronic).
Guideline Reference: OPP Aquatic Life Benchmarks
 
Spatial Representation: The samples were collected at 1 monitoring site: 801SARPCW (Peter's Canyon Wash).
Temporal Representation: The samples were collected between the dates of 2014-05-13 and 2014-05-13
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132700
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Heptachlor epoxide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132700, Heptachlor epoxide
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238302
 
Pollutant: Heptachlor epoxide
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for Heptachlor Epoxide. Data were collected for 2 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite, 1 composite(s) of Freshwater Clam each composed of 85 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for heptachlor epoxide in shellfish tissue is 1.4 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 1999)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Public Health Goal for Heptachlor and Heptachlor Epoxide in Drinking Water
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132701
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Hexachlorobenzene/ HCB
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132701, Hexachlorobenzene/ HCB
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238339
 
Pollutant: Hexachlorobenzene/ HCB
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for Hexachlorobenzene. Data were collected for 2 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite, 1 composite(s) of Freshwater Clam each composed of 85 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for hexachlorobenzene in shellfish tissue is 4.3 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132702
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Lead
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Three lines of evidence is available in the administrative record to assess this pollutant. Four of the 72 water samples exceed the WARM Lead criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Four of the 72 water samples exceed the WARM Lead criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132702, Lead
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239267
 
Pollutant: Lead
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Lead .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for lead is the probable effect concentration (PEC) of 128 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132702, Lead
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82065
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 4
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Four of the 72 samples exceeded the water quality objective for lead.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132702, Lead
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236398
 
Pollutant: Lead
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Lead.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved lead criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 2.5 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132703
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132703, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239363
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for HCH, gamma-. Although a total of 6 samples were collected, 6 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the objective and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for lindane is the probable effect concentration (PEC) for Lindane is 4.99 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Date for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132703, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82066
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for HCH, gamma.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: In freshwater sediments the probable effect concentration (predictive of sediment toxicity for sediment-dwelling organisms) for Lindane (gamma-HCH) is 4.99 ug/Kg dry weight (MacDonald et al. 2000).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
Line of Evidence (LOE) for Decision ID 132703, Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238349
 
Pollutant: Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 2 samples exceeded the water quality threshold for HCH, gamma-. Data were collected for 2 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite, 1 composite(s) of Freshwater Clam each composed of 85 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for lindane in shellfish tissue is 7.1 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 2005)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Air Toxics Hotspots Program Risk Assessment Guidelines. Part ll Technical Support Document for Describing Available Cancer Potency Values.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
153015
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Mercury
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant.

COMM beneficial use:
Zero of 1 shellfish tissue samples exceed the mercury criterion.

WARM beneficial use:
Water - 0 of 27 samples exceed the mercury criterion,
Sediment - 0 of 5 samples exceed the mercury evaluation guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of 27 dissolved water samples exceeded the criterion for COMM beneficial use and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: Decision written by SWRCB staff.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards for the pollutant are not exceeded.
 
 
Line of Evidence (LOE) for Decision ID 153015, Mercury
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82068
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 27
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the 27 samples exceeded the evaluation guideline for mercury.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Surface waters shall not contain concentrations of chemical constituents in amounts that adversely affect any designated beneficial use.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: National Recommended Water Quality Criteria Continuous Concentrations (4-day average concentrations) for freshwater aquatic organisms exposure to elemental mercury is 0.77 ug/L.
Guideline Reference: National Recommended Water Quality Criteria. United States Environmental Protection Agency. Office of Water. Office of Science and Technology
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were intermittently collected from September 2006 until January 2009.
Environmental Conditions: Approximately 40% of the samples were collected after storm events.
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 153015, Mercury
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239372
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 5 samples exceeded the evaluation guideline for Mercury .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for mercury is the probable effect concentration (PEC) of 1.06 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-10-05 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 153015, Mercury
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238255
 
Pollutant: Mercury
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 1 samples exceeded the water quality threshold for Mercury. Data were collected for 1 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The USEPA 304(a) recommended water quality criterion for concentrations of methylmercury in shellfish tissue (wet weight) is 0.20 ppm. (Brodberg, R.K., and G.A. Pollock, 1999; USEPA, 2001)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Water Quality Criterion for the Protection of Human Health: Methylmercury. Final. United States Environmental Protection Agency Office of Science and Technology Office of Water. EPA-823-R-01-001. January 2001
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2016-06-06 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132704
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Methyl Parathion
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132704, Methyl Parathion
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239539
 
Pollutant: Methyl Parathion
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for Parathion, Methyl .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for methyl parathion is the median lethal concentration (LC50) of 6 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 6 ug/g is the geometric mean of LC50 values for methyl parathion from Ding et al., (2011).
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132705
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Mirex
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132705, Mirex
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238562
 
Pollutant: Mirex
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Waterboard staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: Zero of Zero samples exceeded the water quality threshold for Mirex. Although data was collected for 2 fish species (1 composite(s) of Corbicula spp. each composed of 1 fish per composite, 1 composite(s) of Freshwater Clam each composed of 85 fish per composite), all 2 sample(s) had to be thrown out due to quantitation issues.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for mirex in shellfish tissue is 0.43 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008; OEHHA, 1992)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
Guideline Reference: Expedited Cancer Potency Values and Proposed Regulatory Levels for Certain Proposition 65 Carcinogens.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2016-06-06. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132706
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Nickel
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero of the 73 water samples exceed the WARM Nickel criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero of the 73 water samples exceed the WARM Nickel criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132706, Nickel
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239297
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Nickel .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for nickel is the probable effect concentration (PEC) of 48.6 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132706, Nickel
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82037
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the 72 samples exceeded the water quality objective for nickel.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132706, Nickel
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236679
 
Pollutant: Nickel
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Nickel.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved nickel criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 52 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132707
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Oxygen, Dissolved
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Two of the 113 samples exceed the WARM dissolved oxygen objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of 113 samples exceeded the WARM dissolved oxygen objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237037
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237017
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801SARPCW (Peter's Canyon Wash).
Temporal Representation: The samples were collected between the dates of 2014-05-13 and 2014-05-13
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237018
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 10
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 10 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2018-10-29 and 2019-09-18
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237084
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82039
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 84
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Numeric data generated from 84 minimums of Dissolved Oxygen concentrations had no exceedences.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of all surface waters designated as "Warm Freshwater Habitat" must be greater than 5.0 mg/L.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the BARSED and BPF06 stations.
Temporal Representation: Samples were collected approximately once a week from July 2006 to June 2009.
Environmental Conditions:
QAPP Information: NPDES quality assurance.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236840
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCWT01 (Peter's Canyon Wash at Barranca).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237011
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 11
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 11 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2016-06-13 and 2017-06-06
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237466
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 2 of 2 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801XXX305 (Peters Canyon Wash Random Olsen Site 305).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2014-06-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236993
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCW171 (Peters Canyon Wash Random Olsen Site 171).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132707, Oxygen, Dissolved
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236947
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Oxygen, Dissolved.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved oxygen content of surface waters shall not be depressed below 5 mg/L for waters designated WARM as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCWT02 (Peter's Canyon Wash Below Fwy 5).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132709
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: PCBs (Polychlorinated biphenyls)
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132709, PCBs (Polychlorinated biphenyls)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239568
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 6
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 6 samples exceeded the evaluation guideline for PCBs (Polychlorinated biphenyls) .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for total PCBs is the probable effect concentration (PEC) of 676 ug/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132709, PCBs (Polychlorinated biphenyls)
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238491
 
Pollutant: PCBs (Polychlorinated biphenyls)
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Shellfish
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows 0 of the 1 samples exceeded the water quality threshold for PCBs (Polychlorinated biphenyls). Data were collected for 1 fish species (1 composite(s) of Freshwater Clam each composed of 85 fish per composite).
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The modified OEHHA Fish Contaminant Goal for polychlorinated biphenyls in shellfish tissue is 3.9 ppb. This screening level assumes an average body weight of 70 kg and a consumption rate of 21 g/day for a 30 year exposure over a 70-year lifetime. This constituent is a carcinogen therefore the risk level is set to one in a million. (Brodberg, R.K., and G.A. Pollock, 1999; Klasing, S., and R. Brodberg, 2008)
Guideline Reference: Prevalence of Selected Target Chemical Contaminants in Sport Fish From Two California Lakes: Public health designed screening study. Sacramento, CA: Office of Environmental Health Hazard Assessment
Guideline Reference: Development of Fish Contaminant Goals and Advisory Tissue Levels for Common Contaminants in California Sport Fish: Chlordane, DDTs, Dieldrin, Methylmercury, PCBs, Selenium, and Toxaphene
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SARPCW (Peter's Canyon Wash).
Temporal Representation: Data for this line of evidence were collected between 2014-06-05 and 2014-06-05. When composited fish were collected over multiple days, the first day of fish collection was used as the sample date in the LOE, both for LOE writing, and for averaging period purposes.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132725
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Permethrin
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Insufficient information is available to determine beneficial use support for this waterbody-pollutant combination with the statistical power and confidence required by the Listing Policy. Beneficial use support will be reassessed in a future cycle, if more data are available
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of the available data and information, SWRCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.
 
 
Line of Evidence (LOE) for Decision ID 132725, Permethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237334
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Permethrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The chronic criterion for permethrin is 1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of permethrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Permethrin
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132725, Permethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239475
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Permethrin, Total .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin (Amweg et al., 2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132725, Permethrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82040
 
Pollutant: Permethrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Permethrin, Total.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for permethrin is the median lethal concentration (LC50) of 8.9 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 8.9 ug/g is the geometric mean of LC50 values for permethrin from Amweg et al. (2005).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
132711
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Temperature, water
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

Ten lines of evidence are available in the administrative record to assess this pollutant. Two of the 175 samples exceed the WARM temperature objective.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of 175 samples exceeded the WARM temperature objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238022
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 12
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Santa Ana River Regional Monitoring Program data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 12 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: P3-OC7 (Peters Canyon Wash downstream of Barranca Parkway).
Temporal Representation: The samples were collected between the dates of 2016-06-13 and 2019-09-18
Environmental Conditions:
QAPP Information: CDM Smith. 2019. Santa Ana River Watershed Bacteria Monitoring Program.
QAPP Information Reference(s): Santa Ana River Watershed Bacteria Monitoring Program
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237965
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238003
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed Newport Bay Watershed Bio Trend Monitor Prgm RWB8 data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Tissue, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801SARPCW (Peter's Canyon Wash).
Temporal Representation: The samples were collected between the dates of 2014-05-13 and 2014-05-13
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238021
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 2 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801XXX305 (Peters Canyon Wash Random Olsen Site 305).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2014-06-02
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237969
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCWT01 (Peter's Canyon Wash at Barranca).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237933
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCWT02 (Peter's Canyon Wash Below Fwy 5).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 28938
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 68
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Of the 68 samples collected, 0 exceeded the Basin Plan Objective.
Data Reference: Orange County Coast Keeper Coastal Watersheds Project
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Temperature objectives for natural receiving water are specified in the ¿Water Quality Control Plan.¿ The natural receiving water temperature of inland surface waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such alteration in temperature does not adversely affect beneficial uses. The temperature of waters designated WARM shall not be raised above 90°F June through October or above 78°F during the rest of the year as a result of controllable water quality factors.
Objective/Criterion Reference: Water Quality Control Plan for the Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at two stations: Peter's Canyon Channel 1, Peter's Canyon Channel 2
Temporal Representation: The samples were collected monthly starting on 3/9/2004 through 3/29/2006.
Environmental Conditions:
QAPP Information: The data's quality is deemed acceptable because it was collected under the auspices of a Regional Board staff's approved quality assurance plan.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82050
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 87
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Numeric data generated from 87 averages of temperature had 2 exceedences.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: At no time shall warm freshwater habitat-designated waters be raised above 80 degrees Fahrenheit as a result of waste discharges.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Samples were collected from the BARSED and BPF06 stations.
Temporal Representation: Samples were collected approximately twice a month from July 2006 to June 2009.
Environmental Conditions:
QAPP Information: NPDES quality assurance.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238002
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP RWB8 Monitoring data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801PCW171 (Peters Canyon Wash Random Olsen Site 171).
Temporal Representation: The samples were collected between the dates of 2012-06-19 and 2012-06-19
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132711, Temperature, water
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238128
 
Pollutant: Temperature, water
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Temperature.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The temperature of waters designated WARM shall not be raised above 90 degrees F June through October or above 78 degrees F during the rest of the year as a result of controllable water quality factors (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: The samples were collected between the dates of 2014-06-16 and 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132713
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Zinc
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. Zero (0) of the seventy-three (73) water samples exceed the beneficial use criterion. Zero (0) of the four (4) sediment samples exceed the guideline.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of the seventy-two (72) water samples exceed the beneficial use criterion and zero (0) of the four (4) sediment samples exceed the guideline and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132713, Zinc
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82063
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the 72 samples exceeded the water quality objective for zinc.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132713, Zinc
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 237943
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Zinc.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved zinc criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 120 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132713, Zinc
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239448
 
Pollutant: Zinc
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Zinc .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for zinc is the probable effect concentration (PEC) of 459 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
132715
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Bifenthrin
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Eight lines of evidence are available in the administrative record to assess this pollutant. Two of the four sediment samples exceed the WARM Bifenthrin guideline. Six of six samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the four sediment samples exceed the WARM Bifenthrin guideline. Six of six samples exhibited sediment toxicity and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 235699
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support, and the results are as follows: 0 of the 0 samples exceeded the evaluation guideline for Bifenthrin. Although a total of 1 samples were collected, 1 of these samples were not included in the assessment because the laboratory data reporting limit(s) was above the water quality threshold and therefore the results could not be quantified with the level of certainty required by the Listing Policy Section 6.1.5.5.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan for the Santa Ana River Basin).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The chronic criterion for bifenthrin is 0.1 ng/L (expressed as a 4-day average).  If the freely dissolved concentrations of bifenthrin were reported or could be calculated then these values were used for this assessment.  In the absence of freely dissolved concentrations, total concentrations were used.
Guideline Reference: Water Quality Criteria Report for Bifenthrin
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S02947 (Peters Canyon Channel Random SMC Site 02947).
Temporal Representation: Data for this waterbody were collected over the date range 2014-06-16 to 2014-06-16
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82061
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Thirteen samples were collected to evaluate sediment toxicity. Five of the thirteen samples exhibited significant toxicity. The toxicity tests included survival of Hyallela.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. The t-test is used to determine if there is a statistically significant decrease in organism response in the sample as compared to the control. Exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Assessing the Toxicity of Sediment-associated Contaminants with Estuarine and Marine Amphipods. June 1994. EPA 600/R-94/025
 
Spatial Representation: The samples were collected in Peters Canyon Wash.
Temporal Representation: The samples were collected from approximately three times a year from 2006 to 2010.
Environmental Conditions:
QAPP Information: The data collected under the Quality Assurance Management Plan for The Orange County Stormwater Program. The SWAMP measurement quality objectives were followed for toxicity data. The performance of toxicity bioassays and evaluation of reference toxicants were performed using USEPA and Standard Methods.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82062
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: One sample was collected to evaluate sediment toxicity. The sample exhibited significant toxicity. The toxicity test included survival and growth of Hyalella azteca. One sample can have multiple toxicity test results but will be counted only once. One sample is defined as being collected on the same day at the same location with the same lab sample id (if provided).
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses. Region 8 Basin Plan.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: Toxicity is defined as a statistically significant effect in the sample exposure compared to the control using EPA-recommended hypothesis testing. For SWAMP data exceedances are counted with the significant effect code SL. SL is defined as the result being significant compared to the negative control based on a statistical test, less than stated the alpha level, AND less than the evaluation threshold.
Guideline Reference: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-associated Contaminants with Freshwater Invertebrates, Second Edition. U.S. Environmental Protection Agency Office of Research and Development, Duluth, MI , U.S. Environmental Protection Agency Office of Water, Washington, DC EPA-600/R-99/064
 
Spatial Representation: The sample was collected at station 801SUP065 (Peter's Canyon Wash at Warner).
Temporal Representation: The sample was collected in January 2007.
Environmental Conditions:
QAPP Information: All data was collected following the Standard Operating Procedures and Data Quality Objectives outlined in the SWAMP QAMP, (Puckett, 2002). QA data are included in submission.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238154
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus for Growth (wt/surv indiv), Hyalella azteca for Survival, Chironomus dilutus for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30, Chironomus dilutus for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT02 ( Peter's Canyon Wash Below Fwy 5 ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238156
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT01 ( Peter's Canyon Wash at Barranca ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238164
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 5 samples collected by SWAMP Stream Pollution Trends for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-05-26, Hyalella azteca for Survival on 2011-10-05, Hyalella azteca for Survival on 2012-01-18, Hyalella azteca for Survival on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2013-01-11, Hyalella azteca for Survival on 2013-01-11.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801SDCALT ( San Diego Creek at Alton Parkway ).
Temporal Representation: The samples were collected between the dates of 2011-05-26 and 2013-01-11.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238723
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 1 of the 3 samples exceeded the evaluation guideline for Bifenthrin .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin (Amweg et al., 2005 and Amweg and Weston, 2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132715, Bifenthrin
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82121
 
Pollutant: Bifenthrin
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP data for Peters Canyon Channel to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Bifenthrin.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for bifenthrin is the median lethal concentration (LC50) of 0.43 ug/g and is normalized by the percentage of organic carbon in the sediment sample. The LC50 0.43 ug/g is the geometric mean of LC50 values for bifenthrin from Amweg et al. (2005) and Amweg and Weston (2007).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
132695
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Copper
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2018)
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.

Three lines of evidence are available in the administrative record to assess this pollutant. 10 of the 73 samples exceed the WARM Copper criteria.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. 10 of the 73 samples exceed the WARM Copper criteria and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 132695, Copper
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 236050
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed RWB8 So. CA Stormwater Monitoring Coalition data for Peters Canyon Wash (Orange County) to determine beneficial use support and results are as follows: 0 of 1 samples exceeded the water quality threshold for Copper.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The dissolved copper criterion continuous concentration (expressed as a 4-day average) to protect aquatic life in freshwater is hardness dependent. The criterion when calculated using a default hardness of 100 mg/L is 9 ug/L (California Toxics Rule, 2000).
Objective/Criterion Reference: Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: The samples were collected at 1 monitoring site: 801S19286 (Peters Canyon Wash Random SMC Site 19286).
Temporal Representation: The samples were collected between the dates of 2013-06-04 and 2013-06-04
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132695, Copper
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238951
 
Pollutant: Copper
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 0 of the 4 samples exceeded the evaluation guideline for Copper .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for copper is the probable effect concentration (PEC) of 149 mg/kg dry weight (MacDonald et al., 2000a).
Guideline Reference: Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems. Environmental Contamination and Toxicology. 39: 20-31
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2013-01-11
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132695, Copper
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82029
 
Pollutant: Copper
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 10
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Ten of the 72 samples exceeded the water quality objective for copper.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion continuous concentrations (4-day average) to protect aquatic life in freshwater. The disolved criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
 
DECISION ID
132714
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Pyrethroids
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: New Decision
Revision Status Revised
Sources: A Source Unknown
Expected TMDL Completion Date: 2037
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.6 of the Listing Policy. Under section 3.6 at least two lines of evidence are necessary to assess listing status for pollutants sediment, and pollutant concentrations in sediment must be associated with sediment toxicity to justify adding that pollutant to the CWA section 303(d) List.

Four lines of evidence are available in the administrative record to assess this pollutant. Two of the four sediment samples exceed the WARM Pyrethroid guideline. Seven of seven samples exhibited sediment toxicity.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification for placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Two of the four sediment samples exceed the WARM Pyrethroid guideline, and this sample size is sufficient to determine beneficial use support, with the power and confidence of the Listing Policy. There is associated sediment toxicity data as required by Section 3.6 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation:
 
 
Line of Evidence (LOE) for Decision ID 132714, Pyrethroids
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238156
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT01 ( Peter's Canyon Wash at Barranca ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132714, Pyrethroids
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238164
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 5
Number of Exceedances: 5
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 5 of the 5 samples collected by SWAMP Stream Pollution Trends for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Hyalella azteca for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2011-05-26, Hyalella azteca for Survival on 2011-10-05, Hyalella azteca for Survival on 2012-01-18, Hyalella azteca for Survival on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2012-09-12, Hyalella azteca for Growth (wt/surv indiv) on 2013-01-11, Hyalella azteca for Survival on 2013-01-11.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801SDCALT ( San Diego Creek at Alton Parkway ).
Temporal Representation: The samples were collected between the dates of 2011-05-26 and 2013-01-11.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132714, Pyrethroids
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 239621
 
Pollutant: Pyrethroids
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 4
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Water Board staff assessed SWAMP Stream Pollution Trends data for Peters Canyon Wash (Orange County) to determine beneficial use support and the results are as follows: 2 of the 4 samples exceeded the evaluation guideline for Pyrethroids .
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to level which are harmful to human health. The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for the protection of aquatic life from pyrethroids is one toxic unit. Individual pyrethroid concentrations in sediment were normalized to organic carbon content, divided by the respective LC50 and then summed. A sum over over one toxic unit is an exceedance of the evaluation guideline (Amweg et al. 2006).
Guideline Reference: Use and Toxicity of Pyrethroid Pesticides in the Central Valley, California, USA. Environmental Toxicology and Chemistry, 24:966-972, with erratum 24:No. 5
Guideline Reference: Partitioning, bioavailability, and toxicity of the pyrethroid insecticide cypermethrin in sediments. Environmental Toxicology and Chemistry 21:9-15
Guideline Reference: Toxicity of Sediment-Associated Pesticides to Chironomus dilutus and Hyalella azteca. Arch. Environ. Contam. Toxicol. 61:83¿92.
Guideline Reference: Whole-sediment toxicity identification evaluation tools for pyrethroid insecticides: I. piperonyl butoxide addition. Environ. Toxicol. Chem. 26:2389-2396.
Guideline Reference: Compilation of freshwater OC-normalized sediment toxicity data for pyrethroids
Guideline Reference: Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
 
Spatial Representation: Data were collected from 1 station(s). Station Code(s): 801SDCALT (San Diego Creek at Alton Parkway).
Temporal Representation: Data for this waterbody were collected over the date range 2011-05-26 to 2012-09-12
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
Line of Evidence (LOE) for Decision ID 132714, Pyrethroids
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 238154
 
Pollutant: Toxicity
LOE Subgroup: Toxicity
Matrix: Sediment
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: 1 of the 1 samples collected by SWAMP RWB8 Monitoring for Peters Canyon Wash (Orange County) exhibited toxicity. A sample may have multiple toxicity test results, but will only be counted once. A sample is defined as being collected on the same day and the same location. The following organisms and parameters were utilized for the toxicity tests: Chironomus dilutus for Growth (wt/surv indiv), Hyalella azteca for Survival, Chironomus dilutus for Survival, Hyalella azteca for Growth (wt/surv indiv). The following tests exhibited toxicity: Hyalella azteca for Survival on 2019-04-30, Chironomus dilutus for Survival on 2019-04-30.
Data Reference: Field, Habitat, Toxicity, WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 8.
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses (Water Quality Control Plan, Santa Ana Basin, Chapter 4 Water Quality Objectives, Inland Surface Waters).
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The sample is toxic when the response of the organisms exposed to the sample is significantly different (worse) than the response of the organisms exposed to the laboratory control based on statistical hypothesis testing.  An exceedance is counted when the significant effect code is “Significant; Less Similarity,” which means that the sample result is significantly different than the control result, and the percent effect is greater than the evaluation threshold.  The default evaluation threshold is 20% unless otherwise stated.
Guideline Reference: Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms. Fourth Edition. Office of Water, U.S. Environmental Protection Agency. Washington, D.C. EPA-821-R-02-013
 
Spatial Representation: The samples were collected at monitoring site: 801PCWT02 ( Peter's Canyon Wash Below Fwy 5 ).
Temporal Representation: The samples were collected between the dates of 2019-04-30 and 2019-04-30.
Environmental Conditions:
QAPP Information: SWRCB. 2018. This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements..
QAPP Information Reference(s): This is a placeholder reference for data that was collected after QAPP requirements were developed, but exempt from the requirements.
 
 
DECISION ID
98082
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Fipronil
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the zero (0) samples exceed the beneficial use criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of the zero (0) samples exceed the beneficial use criterion and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 98082, Fipronil
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82059
 
Pollutant: Fipronil
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The single sample collected was non-detect. It was not used in the assessment because the laboratory data method detection limit was above the guideline and therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fipronil is the median lethal concentration (LC50) of 0.13 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
98136
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Fipronil Sulfide
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Zero (0) of the zero (0) samples exceed the beneficial use criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of the zero (0) samples exceed the beneficial use criterion and this sample size is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating. A minimum of 16 samples are needed to determine if a beneficial use is fully supported using table 3.1.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list. The readily available data and information is insufficient to determine, with the power and confidence of the Listing Policy, the applicable beneficial use support rating.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 98136, Fipronil Sulfide
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82060
 
Pollutant: Fipronil Sulfide
LOE Subgroup: Pollutant-Sediment
Matrix: Sediment
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: The single sample collected was non-detect. It was not used in the assessment because the laboratory data method detection limit was above the guideline and therefore the result could not be quantified with the level of certainty required by the Listing Policy.
Data Reference: Statewide Project Urban Pyrethroid Status Monitoring
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan for the Santa Ana Region (SARWQCB 2008): The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The evaluation guideline for fipronil sulfide is the median lethal concentration (LC50) of 0.16 ug/g and is normalized by the percentage of organic carbon in the sediment sample (Maul et al. 2008).
Guideline Reference: Effect of sediment-associated pyrethroids, fipronil, and metabolites on Chironomus tentans growth rate, body mass, condition index, immobilization, and survival. Environ. Toxicol. Chem. 27(12):2582-2590.
 
Spatial Representation: Data for this line of evidence for Peters Canyon Channel was collected at 1 monitoring site [ Peter's Canyon Wash @ Warner station (801SUP065).]
Temporal Representation: Data was collected on a single day 1/7/2007.
Environmental Conditions: Staff is not aware of any special conditions that might affect interpretation of the data.
QAPP Information: SWAMP data collected before September 2008 followed the QAMP (2002).
QAPP Information Reference(s): Quality Assurance Management Plan for the State of California's Surface Water Ambient Monitoring Program. Sacramento, CA. State Water Resources Control Board. SWAMP. December 2002 (1st version)
 
 
DECISION ID
98257
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Silver
Final Listing Decision: Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: Do Not List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

Two lines of evidence are available in the administrative record to assess this pollutant. Zero (0) of the seventy-two (72) samples exceed the beneficial use criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the CWA section 303(d) List in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Zero (0) of the seventy-two (72) samples exceed the beneficial use criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 98257, Silver
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82049
 
Pollutant: Silver
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 72
Number of Exceedances: 0
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: None of the 72 samples exceeded the water quality objective for silver.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic pollutants in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: California Toxics Rule (CTR) lists criterion maximum concentrations for silver to protect aquatic life in freshwater (1-hour average). The disolved silver criterion in freshwater is hardness dependent for each sample and varies based on the ambient hardness during sampling. Section (b)(1) in CTR contains the hardness dependent formula for the metals criterion. If no hardness data were available, a value of 100 mg/L was used.
Guideline Reference: Code of Federal Regulations 40 part 131.38 Establishment of numeric criteria for priority toxic pollutants for the State of California. 7/1/2011 Edition
 
Spatial Representation: Samples were collected from Peters Canyon Wash at stations BARSED and BPF06.
Temporal Representation: Samples were collected intermittently at station BARSED from July 2006 until June 2009 and from station BPF06 in 2006 & 2007 once in October and once in May.
Environmental Conditions:
QAPP Information: Samples were collected and analyzed in accordance with the signed and certified, Quality Assurance Management Plan for the Orange County Stormwater Program.
QAPP Information Reference(s):
 
 
DECISION ID
98198
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Malathion
Final Listing Decision: List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (TMDL required list)(2016)
Revision Status Original
Sources: A Source Unknown
Expected TMDL Completion Date: 2027
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant is being considered for placement on the CWA section 303(d) List under section 3.1 of the Listing Policy. Under section 3.1, a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. Six (6) of the sixty-seven (67) samples exceed the beneficial use criterion.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the CWA section 303(d) List.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Six (6) of the sixty-seven (67) samples exceed the beneficial use criterion and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 98198, Malathion
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 82067
 
Pollutant: Malathion
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Total Dissolved
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 67
Number of Exceedances: 6
 
Data and Information Type: Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: Six of sixty seven samples exceed the maximum (Instantaneous) concentration for Malathion in freshwater of 100 ng/L.
Data Reference: Data for Various Waterbodies in Region 8 and Region 9, 2006-2009.
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: The concentrations of toxic substances in the water column, sediments or biota shall not adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan, Santa Ana River Basin
 
Evaluation Guideline: The maximum (Instantaneous) concentration for Malathion in freshwater is 100 ng/L.
Guideline Reference: Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
 
Spatial Representation: Samples were collected at sites: BARSED and BPF06
Temporal Representation: Samples were collected from 2006 to 2009.
Environmental Conditions:
QAPP Information: Data were submitted with the County of Orange Stormwater Program Quality Assurance Management Plan (QAMP) dated January 2010. However, data were collected prior to the development of this QAMP, therefore the quality of these data are unknown.
QAPP Information Reference(s):
 
 
DECISION ID
68189
Region 8     
Peters Canyon Wash (Orange County)
 
Pollutant: Toxaphene
Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: List on 303(d) list (being addressed by USEPA approved TMDL)(2016)
Revision Status Original
Sources: See TMDL documentation
TMDL Name: Newport Bay Watershed Organochlorine Compounds TMDL
TMDL Project Code: 161
Date TMDL Approved by USEPA: 11/12/2013
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: This pollutant was placed on the section 303(d) list in a previous assessment cycle. No new information was reviewed for the current assessment cycle. Therefore, the previous conclusion remains unchanged; however, a TMDL has been developed and approved by USEPA and the approved implementation plan is expected to result in full attainment of the standard within a specified time frame. The previous conclusion is as follows:

This pollutant is being considered for placement on the section 303(d) list under section 3.5 of the Listing Policy. One line of evidence is available in the administrative record to assess this pollutant.

Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.

This conclusion is based on the staff findings that:
1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy.
2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy.
3. Nine of the 14 samples exceeded the NAS Guideline and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy.
4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
 
Regional Board Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current. The decision has not changed.
 
State Board Review of Regional Board Conclusion and Recommendation:
 
State Board Decision Recommendation: After review of this Regional Board decision, SWRCB staff recommend the decision be approved by the State Board.
 
 
Line of Evidence (LOE) for Decision ID 68189, Toxaphene
Region 8     
Peters Canyon Wash (Orange County)
 
LOE ID: 2987
 
Pollutant: Toxaphene
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Warm Freshwater Habitat
 
Number of Samples: 14
Number of Exceedances: 9
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Nine out of 14 samples exceeded. A total of 13 whole fish composite samples of red shiner and one whole fish composite of fathead minnow were collected. Red shiner samples were collected in 1992-2002. Flathead minnow sample was collected in 2001. The guideline was exceeded in 1992-98 samples of red shiner. Samples from 1999-2002 did not exceed the guideline (TSMP, 2002).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Santa Ana River Basin RWQCB Basin Plan: Toxic substances shall not be discharged at levels that will bioaccumulate in aquatic resources to levels which are harmful to human health.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 100 ng/g [NAS Guideline (whole fish)] (NAS, 1972).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station located upstream from Irvine Center Parkway Bridge.
Temporal Representation: Samples were collected annually from 1992-2002.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 and 1994-95 Data Reports.

Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 1996-2000. Department of Fish and Game.

Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 2001-2002. Department of Fish and Game.
QAPP Information Reference(s):