Draft California 2020 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 6 - Lahontan Region

Water Body Name:	Cinder Cone Springs
Water Body ID:	CAW6352001019990129120047
Water Body Type:	Wetland, Freshwater


DECISION ID	80296	Region 6
Cinder Cone Springs

Pollutant:	Nitrogen, Nitrate
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Revised
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for removal from the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. Effluent disposal to the Cinder cone ended when the Tahoe-Truckee Sanitation Agency's (TTSA) regional wastewater treatment plant (WWTP) became operational in 1978. 2. The reliability of the quality of the data collected in 1969 (which was partially used as a basis for the original listing) is unknown. 3. In 1977, 3 out of 11 samples exceeded the current MCL for Nitrate. 4. Over 25 years passed since the practice which caused the impairment ceased and before any new data was collected in this area to assess water quality. The 1969 and 1977 data are no longer reflective of current conditions in Cinder Cone Springs and it is presumed that standards are now met since Regional Board staff are not aware of conditions or information indicating impairment to these beneficial uses related to the constituents for which the springs are listed. 5. According to the 2003 monitoring data (which is the only data we have relevant to the current conditions at Cinder Cone Springs), none of the 6 samples exceed the MCL for Nitrate.

Regional Board Decision Recommendation:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

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 80296, Nitrogen, Nitrate	Region 6
Cinder Cone Springs

LOE ID:

3437

Pollutant:

Nitrate as Nitrate (NO3)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

1969 Baseline data for Cinder Cone Springs (data collected prior to sewage effluent being discharged in to the Cinder Cone). 4 out of 25 samples exceed the MCL for Nitrate as Nitrate (LRWQCB, 2004b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

MCL for Nitrate as Nitrate, 45 mg/L.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

"Springs draining the Cinder Cone disposal site".

Temporal Representation:

Data collected in 1969.

Environmental Conditions:

The Cinder cone was used by the North Tahoe and Tahoe City Public Utility Districts (PUDs) to dispose of sewage effluent from the Lake Tahoe basin from April 1970 to February 1978.

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 80296, Nitrogen, Nitrate	Region 6
Cinder Cone Springs

LOE ID:

3436

Pollutant:

Nitrate as Nitrate (NO3)

LOE Subgroup:

Pollutant-Water

Matrix:

Not Specified

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

1. Effluent disposal to the Cinder cone ended when the Tahoe-Truckee Sanitation Agency's (TTSA) regional wastewater treatment plant (WWTP) became operational in 1978.
2. The reliability of the quality of the data collected in 1969 (which was partially used as a basis for the original listing) is unknown.
3. In 1977, 3 out of 11 samples exceeded the current MCL for Nitrate.
4. Over 25 years passed since the practice which caused the impairment ceased and before any new data was collected in this area to assess water quality. The 1969 and 1977 data are no longer reflective of current conditions in Cinder Cone Springs and it is presumed that standards are now met since Regional Board staff are not aware of conditions or information indicating impairment to these beneficial uses related to the constituents for which the springs are listed.
5. According to the 2003 monitoring data (which is the only data we have relevant to the current conditions at Cinder Cone Springs), none of the 6 samples exceed the MCL for Nitrate (LRWQCB, 2004b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Temporal Representation:

Environmental Conditions:

Cinder Cone Springs are included on the Clean Water Act Section 303(d) list of impaired waters due to elevated measurements of total dissolved solids, nutrients, chlorides and salinity. Percolation trenches in a volcanic cinder cone in the vicinity of Cinder Cone Springs were used for land disposal of primary-treated sewage effluent in the 1970s, contributing pollutants to the groundwater-fed springs. Sewage disposal in the area has not occurred since 1978, and the data that led to the 303(d) listing is over 25 years old. Regional Board staff investigated the water
quality of Cinder Cone Springs in 2003 and found that natural attenuation has been effective in restoring the springs to conditions equal to or better than those reported before sewage discharge began. This report summarizes and compares the available data on historical and current water quality for the springs and recommends that Cinder Cone Springs be removed from the 303(d) list of impaired waters.

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 80296, Nitrogen, Nitrate	Region 6
Cinder Cone Springs

LOE ID:

3438

Pollutant:

Nitrate as Nitrate (NO3)

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

None of the 6 samples exceed the MCL for Nitrate as Nitrate (LRWQCB, 2004b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

MCL for Nitrate as Nitrate, 45 mg/L.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

R4 Spring at Bunker Drive, Tahoe City Lat. 39.175890 - Lon. 120.147754
R5 Spring Box near Twin Crags Access Road Lat. 39.164355 -1 Lon. 20.161009
R13 Spring near water tank on Western States Trail Bridge Lat. 39.197210 -Lon. 120.194524

Temporal Representation:

Samples collected on July 3, 2003 and October 10, 2003.

Environmental Conditions:

The Cinder cone was used by the North Tahoe and Tahoe City Public Utility Districts (PUDs) to dispose of sewage effluent from the Lake Tahoe basin from April 1970 to February 1978.

QAPP Information:

Sampling protocols and quality assurance/control procedures followed the USGS National Field Manual for the Collection of Water Quality Data.

QAPP Information Reference(s):


DECISION ID	68831	Region 6
Cinder Cone Springs

Pollutant:	Salinity/TDS/Chlorides
Final Listing Decision:	Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision:	Delist from 303(d) list (TMDL required list)(2016)
Revision Status	Original
Reason for Delisting:	Applicable WQS attained; reason for recovery unspecified
Impairment from Pollutant or Pollution:	Pollutant

Regional Board Conclusion:	Regional Board Conclusion: This pollutant was considered for removal from the section 303(d) list in a previous assessment cycle. The two LOEs were combined to determine the final use support rating. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of removing this water segment-pollutant combination from the 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. None of 34 samples exceeded the MCL for TDS, and there are no criteria for salinity and chlorides for this water body. 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:	This region was not assessed this cycle. All decisions have been carried over from the previous cycle and remain the same.

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 68831, Salinity/TDS/Chlorides	Region 6
Cinder Cone Springs

LOE ID:

3440

Pollutant:

Salinity/TDS/Chlorides

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

Dissolved

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Staff report which summarizes and compares the available data on historical and current water quality for the springs and recommends that Cinder Cone Springs be removed from the 303(d) list of impaired waters. None of the 6 samples taken in 2003 exceed the recommended MCL for TDS (LRWQCB, 2004b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Recommended MCL for TDS is 500 mg/L. No criteria available for Chloride and salinity for this water body.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

None of the 6 samples exceed the recommended MCL for TDS.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

R4 Spring at Bunker Drive, Tahoe City: Lat. 39.175890 - Lon. 120.147754
R5 Spring Box near Twin Crags Access Road: Lat. 39.164355 - Lon. 120.161009
R13 Spring near water tank on Western States Trail Bridge:Lat. 39.197210 - Lon.120.194524

Temporal Representation:

Samples taken on July 3, 2003 and October 10, 2003.

Environmental Conditions:

The Cinder cone was used by the North Tahoe and Tahoe City Public Utility Districts (PUDs) to dispose of sewage effluent from the Lake Tahoe basin from April 1970 to February 1978.

QAPP Information:

Sampling protocols and quality assurance/control procedures followed the USGS National Field Manual for the Collection of Water Quality Data.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68831, Salinity/TDS/Chlorides	Region 6
Cinder Cone Springs

LOE ID:

3439

Pollutant:

Salinity/TDS/Chlorides

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

None

Beneficial Use:

Municipal & Domestic Supply

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

1969 Baseline data for Cinder Cone Springs (data collected prior to sewage effluent being discharged in to the Cinder Cone). None of the 28 samples exceed the recommended MCL for TDS (LRWQCB, 2004b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Recommended MCL for TDS is 500 mg/L. No specific criteria available for Chloride and salinity for this water body.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

"Springs draining the Cinder Cone disposal site".

Temporal Representation:

Samples collected in 1969.

Environmental Conditions:

The Cinder cone was used by the North Tahoe and Tahoe City Public Utility Districts (PUDs) to dispose of sewage effluent from the Lake Tahoe basin from April 1970 to February 1978.

QAPP Information:

QA Info Missing

QAPP Information Reference(s):