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

Supporting Information

Regional Board 2 - San Francisco Bay Region

Water Body Name:	Islais Creek Channel
Water Body ID:	CAE2044001020020129151927
Water Body Type:	Estuary


DECISION ID	151515	Region 2
Islais Creek Channel

Pollutant:	Ammonia
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 section 303(d) list under sections 4.6 of the Listing Policy. Under section 4.6 a single line of evidence is necessary to assess delisting status. Five lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6, the site has significant sediment toxicity and the pollutant concentration not exceeds the sediment guideline. The Consolidated Plan is not sufficiently developed to address this problem. 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 section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. All samples exceeded the sediment guideline and all samples exhibit toxicity. This exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 5. 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 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 151515, Ammonia	Region 2
Islais Creek Channel

LOE ID:

464

Pollutant:

Ammonia

LOE Subgroup:

Narrative Description Data

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

The BPTCP Consolidated Toxic Hot Spots Cleanup Plan presents a variety of corrective actions that need to be completed in order for the cove to be remediated. Responsible parties have been identified.

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:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151515, Ammonia	Region 2
Islais Creek Channel

LOE ID:

466

Pollutant:

Ammonia

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Two samples, both showed significant toxicity in purple urchin tests (Hunt et al., 1998a).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms.

There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Reference envelope approach was used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Samples taken from one location.

Temporal Representation:

Samples collected in September 1994.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151515, Ammonia	Region 2
Islais Creek Channel

LOE ID:

461

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 3 of 4 samples (75%). Significant urchin toxicity in 4 of 5 samples (80%) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151515, Ammonia	Region 2
Islais Creek Channel

LOE ID:

462

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 7 of 18 samples (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

There shall be no chronic toxicity in ambient waters. Chronic toxicity is a detrimental biological effect on growth rate, reproduction, fertilization success, larval development, population abundance, community composition, or any other relevant measure of the health of an organism, population, or community.

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

Samples were collected in both wet and dry seasons.

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson, et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151515, Ammonia	Region 2
Islais Creek Channel

LOE ID:

463

Pollutant:

Estuarine Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Relative benthic index = 0.22, 0.25, 0.43 (3 benthic gradient samples) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Evaluation of the benthic data were completed using the approaches developed by scientists associated with the BPTCP. The relative benthic index used is a calculated value considering the total fauna, total mollusk species, crustacean species and indicator species at a site. The index ranges from 0 to 1.0. An index value of less than or equal to 0.3 is an indication that pollutants or other factors are negatively impacting the benthic community.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151515, Ammonia	Region 2
Islais Creek Channel

LOE ID:

465

Pollutant:

Ammonia

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Two samples exceeding the thresholds in two total measurements using purple sea urchin tests (Hunt et al., 1998a).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Effect thresholds for BPTCP toxicity test protocols (unionized ammonia)
Purple Urchin Development NOEC 0.07 mg/L (Bay et al., 1993)
Purple Urchin Fertilization NOEC >1.4 mg/L (Bay et al., 1993)

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was concurrently collected from samples tested for toxicity.

Temporal Representation:

Data was collected in September 1994.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):


DECISION ID	151250	Region 2
Islais Creek Channel

Pollutant:	Chlordane
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 section 303(d) list under sections 4.6 and 4.10 of the Listing Policy. Under section 4.6 a single line of evidence is necessary to assess delisting status while under section 4.10, a minimum of two lines of evidence are needed to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6, the site has significant sediment toxicity and the pollutant concentration not exceeds the sediment guideline. The benthic community is impacted. 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 section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. Nineteen of 49 samples exceeded the 6 ng/g ERM sediment quality guideline, 14 of 27 samples exhibit toxicity, and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy. The benthic community in this water body is impacted and this pollutant is associated with this impact. 5. 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 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 151250, Chlordane	Region 2
Islais Creek Channel

LOE ID:

450

Pollutant:

Chlordane

LOE Subgroup:

Narrative Description Data

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

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:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151250, Chlordane	Region 2
Islais Creek Channel

LOE ID:

452

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Eighteen of 46 samples exceed the ERM (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

ERM of 6 ng/g used (Long and Morgan, 1990).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP. All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151250, Chlordane	Region 2
Islais Creek Channel

LOE ID:

451

Pollutant:

Chlordane

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

One of 3 samples exceeded ERM (Hunt et al, 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

ERM of 6 ng/g used (Long and Morgan, 1990).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was collected at same locations as benthic community and toxicity samples.

Temporal Representation:

Data was collected in 1997.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151250, Chlordane	Region 2
Islais Creek Channel

LOE ID:

463

Pollutant:

Estuarine Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Relative benthic index = 0.22, 0.25, 0.43 (3 benthic gradient samples) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151250, Chlordane	Region 2
Islais Creek Channel

LOE ID:

462

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 7 of 18 samples (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

Samples were collected in both wet and dry seasons.

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson, et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151250, Chlordane	Region 2
Islais Creek Channel

LOE ID:

461

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 3 of 4 samples (75%). Significant urchin toxicity in 4 of 5 samples (80%) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):


DECISION ID	151251	Region 2
Islais Creek Channel

Pollutant:	Dieldrin
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 section 303(d) list under sections 4.6 and 4.9 of the Listing Policy. Under section 4.6 a single line of evidence is necessary to assess delisting status while under section 4.9, a minimum of two lines of evidence are needed to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6, the site has significant sediment toxicity and the pollutant concentration exceeds the sediment guideline. The benthic community is impacted. 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 section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. Seven of 49 samples exceeded the 8 ng/g ERM sediment quality guideline, 14 of 27 samples exhibit toxicity, and these exceed the allowable frequency listed in Table 4.1 of the Listing Policy. The benthic community in this water body is impacted and this pollutant is associated with this impact. 5. 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 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 151251, Dieldrin	Region 2
Islais Creek Channel

LOE ID:

453

Pollutant:

Dieldrin

LOE Subgroup:

Narrative Description Data

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

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:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151251, Dieldrin	Region 2
Islais Creek Channel

LOE ID:

455

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Six of 46 samples exceeded the ERM (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

ERM of 8 ng/g used (Long et al., 1995).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Samples were collected between 1998 and 2000.

Environmental Conditions:

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP. All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151251, Dieldrin	Region 2
Islais Creek Channel

LOE ID:

463

Pollutant:

Estuarine Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Relative benthic index = 0.22, 0.25, 0.43 (3 benthic gradient samples) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151251, Dieldrin	Region 2
Islais Creek Channel

LOE ID:

454

Pollutant:

Dieldrin

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

One of 3 samples exceeded ERM (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

ERM of 8 ng/g used (Long et al., 1995).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was collected at same locations as benthic community and toxicity samples.

Temporal Representation:

Data was collected in 1997.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151251, Dieldrin	Region 2
Islais Creek Channel

LOE ID:

461

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 3 of 4 samples (75%). Significant urchin toxicity in 4 of 5 samples (80%) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151251, Dieldrin	Region 2
Islais Creek Channel

LOE ID:

462

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 7 of 18 samples (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

Samples were collected in both wet and dry seasons.

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson, et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):


DECISION ID	151252	Region 2
Islais Creek Channel

Pollutant:	Hydrogen Sulfide
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 section 303(d) list under sections 4.6 of the Listing Policy. Under section 4.6 a single line of evidence is necessary to assess delisting status. Two lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6, the site has significant sediment toxicity and the pollutant concentration does not exceed the sediment 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 section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. All samples in the two lines of evidence exhibited significant toxicity and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 5. 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 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 151252, Hydrogen Sulfide	Region 2
Islais Creek Channel

LOE ID:

458

Pollutant:

Hydrogen Sulfide

LOE Subgroup:

Narrative Description Data

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

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:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151252, Hydrogen Sulfide	Region 2
Islais Creek Channel

LOE ID:

459

Pollutant:

Hydrogen Sulfide

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

Total

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Six samples exceeding the threshold in six total measurements. Eohaustorius and purple urchin tests (Hunt et al., 1998a).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Effect thresholds for BPTCP toxicity test protocols
Eohaustorius LOEC 0.114 mg/L (Knezovich et al., 1996)
Mytilus LOEC 0.0053 mg/L (Hunt et al., 1998)
Rhepoxynius LOEC 0.087 mg/L (Hunt et al,. 1998)
Purple Urchin Development LOEC 0.0076 mg/L (Knezovich et al., 1996)
Purple Urchin Fertilization LOEC 0.007-0.014 NOEC (Bay et al., 1993)

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was concurrently collected from samples tested for toxicity.

Temporal Representation:

Data was collected in September 1994.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (SWRCB, 1994).

QAPP Information Reference(s):


DECISION ID	151584	Region 2
Islais Creek Channel

Pollutant:	PAHs (Polycyclic Aromatic Hydrocarbons)
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:	303(d) listing decisions made prior to 2006 were not held in an assessment database. The Regional Boards will update this decision when new data and information become available and are assessed.

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 151584, PAHs (Polycyclic Aromatic Hydrocarbons)	Region 2
Islais Creek Channel

LOE ID:

3754

Pollutant:

PAHs (Polycyclic Aromatic Hydrocarbons) (sediment)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

Not Recorded

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006.

Data Reference:

Placeholder reference pre-2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Evaluation Guideline:

Guideline Reference:

Spatial Representation:

Unspecified

Temporal Representation:

Unspecified

Environmental Conditions:

Unspecified

QAPP Information:

Unspecified

QAPP Information Reference(s):


DECISION ID	151253	Region 2
Islais Creek Channel

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 303(d) list under sections 4.6, and 4.10 of the Listing Policy. Under section 4.6 a single line of evidence is necessary to assess delisting status while under section 4.10, a minimum of two lines of evidence are needed to assess delisting status. Six lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6 the site has significant sediment toxicity but there is insufficient information to determine whether the pollutant contributes to the toxic effects. The benthic community may be impacted by this pollutant. A remedial program has scheduled actions to address this pollutant water body combination. Based on the readily available data and information for sediments, 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 in the Water Quality Limited Segments category. This pollutant should not be removed from this segment because PCBs have been found to bioaccumulate in fish tissue. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. Two of 49 samples exceeded the sediment guideline and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. Ten of 22 samples exhibited significant amphipod toxicity, 4 of five samples exhibited significant sea urchin toxicity and the benthic community is considered to be degraded. 5. Pursuant to section 3.11 of the Listing Policy, PCBs have been listed throughout the Bay because of concerns with bioaccumulation in fish tissue.

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 151253, Toxicity	Region 2
Islais Creek Channel

LOE ID:

462

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 7 of 18 samples (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

Samples were collected in both wet and dry seasons.

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson, et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151253, Toxicity	Region 2
Islais Creek Channel

LOE ID:

463

Pollutant:

Estuarine Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Relative benthic index = 0.22, 0.25, 0.43 (3 benthic gradient samples) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 151253, Toxicity	Region 2
Islais Creek Channel

LOE ID:

461

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 3 of 4 samples (75%). Significant urchin toxicity in 4 of 5 samples (80%) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):


DECISION ID	148992	Region 2
Islais Creek Channel

Pollutant:	Indicator Bacteria
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 sections 2.2 and 3.3 of the Listing Policy. Under section 3.3 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. Ninety-five out of two hundred and forty-five samples exceeded the geometric mean bacteria objective. 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. 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. Ninety-five out of two hundred and forty-five samples exceed the bacteria objectives and this exceeds 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 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 148992, Indicator Bacteria	Region 2
Islais Creek Channel

LOE ID:

300221

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

GeoMean

Beneficial Use:

Water Contact Recreation

Number of Samples:

245

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BeachWatch_San Francisco County data for Islais Creek to determine beneficial use support and the results are as follows: 95 of the 245 samples exceeded the geomean water quality threshold for Enterococcus. This is a six week rolling geomean that is calculated weekly.

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial use where the salinity is 1 ppth or higher 95 percent or more of the time applies a six-week rolling geomean to enterococcus, not to exceed 30 cfu/100mL. (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): BAY#320_SL (BAY#320_SL).

Temporal Representation:

The samples were collected between the days of 2015-10-26 and 2020-10-13 .

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program

Line of Evidence (LOE) for Decision ID 148992, Indicator Bacteria	Region 2
Islais Creek Channel

LOE ID:

299896

Pollutant:

Enterococcus

LOE Subgroup:

Pollutant-Water

Matrix:

Water

Fraction:

STV

Beneficial Use:

Water Contact Recreation

Number of Samples:

Number of Exceedances:

Data and Information Type:

PATHOGEN MONITORING

Data Used to Assess Water Quality:

Water Board staff assessed BeachWatch_San Francisco County data for Islais Creek to determine beneficial use support and the results are as follows: 23 of the 60 samples exceeded the Statistical Threshold Value (STV) water quality threshold for Enterococcus. The STV is based on a 10% exceedance rate that is calculated monthly.

Data Reference:

WQ data from the California Environmental Data Exchange Network assembled for the 2024 Integrated Report in Region 2.

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

The bacteria water quality objective to protect the REC-1 beneficial use where the salinity is 1 ppth or higher 95 percent or more of the time applies a Statistical Threshold Value to enterococcus of 110 cfu/100 mL, not to be exceeded by more than 10 percent of samples collected within in 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): BAY#320_SL (BAY#320_SL).

Temporal Representation:

The samples were collected between the days of 2015-10-26 and 2020-10-13 .

Environmental Conditions:

QAPP Information:

State Board Staff. 2021. QAPP Reference for Beach Watch Program.

QAPP Information Reference(s):

QAPP Reference for Beach Watch Program


DECISION ID	68030	Region 2
Islais Creek Channel

Pollutant:	Endosulfan sulfate
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:	This pollutant is being considered for removal from the section 303(d) list under section 4.6 of the Listing Policy. Under section 4.6 two lines of evidence are necessary to assess listing status. Five lines of evidence are available in the administrative record to assess this pollutant. A sediment guideline is not available and it cannot be determined if the pollutant is likely to cause or contribute to the toxic effect or tot he benthic effects. 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. A sediment quality guideline that complies with the requirements of section 6.1.3 of the Policy is not available. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the 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:	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 68030, Endosulfan sulfate	Region 2
Islais Creek Channel

LOE ID:

456

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Narrative Description Data

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

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:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68030, Endosulfan sulfate	Region 2
Islais Creek Channel

LOE ID:

457

Pollutant:

Endosulfan sulfate

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

Three measurements. Concentration ranges from 3.96 ng/g to 21 ng/g (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

No applicable sediment guideline is available.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was collected over the length of the Creek concurrently with benthic community and toxicity samples.

Temporal Representation:

Data was collected in 1997.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68030, Endosulfan sulfate	Region 2
Islais Creek Channel

LOE ID:

461

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 3 of 4 samples (75%). Significant urchin toxicity in 4 of 5 samples (80%) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68030, Endosulfan sulfate	Region 2
Islais Creek Channel

LOE ID:

462

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 7 of 18 samples (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

Samples were collected in both wet and dry seasons.

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson, et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 68030, Endosulfan sulfate	Region 2
Islais Creek Channel

LOE ID:

463

Pollutant:

Estuarine Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Relative benthic index = 0.22, 0.25, 0.43 (3 benthic gradient samples) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):


DECISION ID	87764	Region 2
Islais Creek Channel

Pollutant:	PCBs (Polychlorinated biphenyls)
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 removal from the 303(d) list under sections 4.6, and 4.10 of the Listing Policy. Under section 4.6 a single line of evidence is necessary to assess delisting status while under section 4.10, a minimum of two lines of evidence are needed to assess delisting status. Six lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6 the site has significant sediment toxicity but there is insufficient information to determine whether the pollutant contributes to the toxic effects. The benthic community may be impacted by this pollutant. A remedial program has scheduled actions to address this pollutant water body combination. Based on the readily available data and information for sediments, 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 in the Water Quality Limited Segments category. This pollutant should not be removed from this segment because PCBs have been found to bioaccumulate in fish tissue. This conclusion is based on the staff findings that: 1. The sediment quality guideline used complies with the requirements of section 6.1.3 of the Policy. 2. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 3. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 4. Two of 49 samples exceeded the sediment guideline and this does not exceed the allowable frequency listed in Table 4.1 of the Listing Policy. Ten of 22 samples exhibited significant amphipod toxicity, 4 of five samples exhibited significant sea urchin toxicity and the benthic community is considered to be degraded. 5. Pursuant to section 3.11 of the Listing Policy, PCBs have been listed throughout the Bay because of concerns with bioaccumulation in fish tissue.

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 87764, PCBs (Polychlorinated biphenyls)	Region 2
Islais Creek Channel

LOE ID:

449

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

One of 46 samples exceeded the sediment quality guideline (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SRBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Sediment guideline of 400 ng/g used (MacDonald et al., 2000).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87764, PCBs (Polychlorinated biphenyls)	Region 2
Islais Creek Channel

LOE ID:

448

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Pollutant-Sediment

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Chemical monitoring of sediments

Data Used to Assess Water Quality:

One of 3 samples exceeded sediment guideline (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Sediment guideline of 400 ng/g used (MacDonald et al., 2000).

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87764, PCBs (Polychlorinated biphenyls)	Region 2
Islais Creek Channel

LOE ID:

462

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 7 of 18 samples (Battelle Memorial Institute, 2002).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data were collected between 1998 and 2000.

Environmental Conditions:

Samples were collected in both wet and dry seasons.

QAPP Information:

Methods used were equivalent to those used in the BPTCP QAPP (Stephenson, et al., 1994). All reported data met QA requirements.

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87764, PCBs (Polychlorinated biphenyls)	Region 2
Islais Creek Channel

LOE ID:

461

Pollutant:

Sediment Toxicity

LOE Subgroup:

Toxicity

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Toxicity testing of sediments

Data Used to Assess Water Quality:

Significant amphipod toxicity in 3 of 4 samples (75%). Significant urchin toxicity in 4 of 5 samples (80%) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

All waters shall be maintained free of toxic substances in concentrations that are lethal to or that produce other detrimental responses in aquatic organisms (SFBRWQCB, 1995).

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

BPTCP Reference envelope approach used.

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan (Stephenson et al., 1994).

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87764, PCBs (Polychlorinated biphenyls)	Region 2
Islais Creek Channel

LOE ID:

447

Pollutant:

PCBs (Polychlorinated biphenyls)

LOE Subgroup:

Narrative Description Data

Matrix:

-N/A

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Not Specified

Data Used to Assess Water Quality:

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:

QAPP Information:

QA Info Missing

QAPP Information Reference(s):

Line of Evidence (LOE) for Decision ID 87764, PCBs (Polychlorinated biphenyls)	Region 2
Islais Creek Channel

LOE ID:

463

Pollutant:

Estuarine Bioassessments

LOE Subgroup:

Population/Community Degradation

Matrix:

Sediment

Fraction:

None

Beneficial Use:

Estuarine Habitat

Number of Samples:

Number of Exceedances:

Data and Information Type:

Benthic macroinvertebrate surveys

Data Used to Assess Water Quality:

Relative benthic index = 0.22, 0.25, 0.43 (3 benthic gradient samples) (Hunt et al., 1998b).

Data Reference:

Placeholder reference 2006 303(d)

SWAMP Data:

Non-SWAMP

Water Quality Objective/Criterion:

Objective/Criterion Reference:

Placeholder reference 2006 303(d)

Evaluation Guideline:

Guideline Reference:

Placeholder reference 2006 303(d)

Spatial Representation:

Data was synoptically collected with benthic community and toxicity measurements over the length of the creek.

Temporal Representation:

Data was collected from 9/94 - 9/97.

Environmental Conditions:

QAPP Information:

BPTCP Quality Assurance Project Plan.

QAPP Information Reference(s):