Final California 2012 Integrated Report( 303(d) List/305(b) Report)

Supporting Information

Regional Board 3 - Central Coast Region

Water Body Name: Oso Flaco Lake
Water Body ID: CAL3121003020011121102545
Water Body Type: Lake & Reservoir
 
DECISION ID
29200
Region 3     
Oso Flaco Lake
 
Pollutant: Nitrate
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2013
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 removed from the section 303(d) list.
 
 
Line of Evidence (LOE) for Decision ID 29200, Nitrate
Region 3     
Oso Flaco Lake
 
LOE ID: 29747
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Preservation of Rare & Endangered Species | Wildlife Habitat
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: CCAMP data collected monthly in Oso Flaco Lake between January 2000 and January 2001 show elevated Nitrate levels which likely contributed to the elevated chlorophyll a concentrations in the water column, wide swings in Dissolved Oxygen concentrations and pH levels. Photo documentation also shows nuisance aquatic vegetation and algae filling the lake in summer months. Nitrate ranged from 28.0 - 31.7 mg/L in monthly grab samples taken from the lake. Dissolved Oxygen measurements (including both monthly grab samples and a single summer time pre-dawn sampling event) ranged from 5.05 mg/L to 21.0 mg/L. This indicates not only depressed but also super saturated oxygen conditions. Chlorophyll a measurements ranged between <1.0 ug/L and 160 ug/L. Three of these measurements were above 40 ug/L, the evaluation guideline used in this assessment.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
  Oso Flaco Lake vegetation photo
  Oso Flaco Lake aquatic vegetation nuisance condition
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Monthly grab samples collected at the culvert between Oso Flaco Lake and Little Oso Flaco Lake (312OFL).
Temporal Representation: Samples were collected by CCAMP staff between January 2000 and Febuary 2001.
Environmental Conditions: Measurements were taken and samples were collected from the down stream side of the culvert between the two lakes. Instream vegetation and algae are very dense in summer months.
QAPP Information: CCAMP data is collected following the SWAMP QAPP.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 29200, Nitrate
Region 3     
Oso Flaco Lake
 
LOE ID: 699
 
Pollutant: Nitrate
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Groundwater Recharge
 
Number of Samples: 0
Number of Exceedances: 0
 
Data and Information Type: Not Specified
Data Used to Assess Water Quality: Sixteen samples were collected (CCAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Basin Plan: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: The 45 mg/L MCL for nitrates should be used.
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: There was one sampling station.
Temporal Representation: There were monthly sampling events.
Environmental Conditions: Fish kills, algae and other evidence of eutrophication have been witnessed by the RWQCB at this site.
QAPP Information: Central Coast Ambient Monitoring Program (CCAMP) QA/QC.
QAPP Information Reference(s):
 
 
DECISION ID
26807
Region 3     
Oso Flaco Lake
 
Pollutant: Ammonia (Unionized)
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 26807, Ammonia (Unionized)
Region 3     
Oso Flaco Lake
 
LOE ID: 9673
 
Pollutant: Ammonia (Unionized)
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 12 samples exceed the criterion for Ammonia as N, Unionized.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin General Objective, Chapter III, Section II.A.2 (General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries) states that the discharge of wastes shall not cause concentrations of unionized ammonia (NH3) to exceed 0.025 mg/l (as N) in receiving waters (page III-4) .
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 2/3/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
26808
Region 3     
Oso Flaco Lake
 
Pollutant: Chlorophyll-a
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 26808, Chlorophyll-a
Region 3     
Oso Flaco Lake
 
LOE ID: 9672
 
Pollutant: Chlorophyll-a
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 16
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 3 of 16 samples exceed the criterion for Chlorophyll a.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect beneficial uses (general objective for biostimulatory substances, Water Quality Control Plan, Central Coast Basin, Chapter III, Section II).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
  North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
  Water quality standards table
 
Evaluation Guideline: North Carolina Administrative code (NCAC), Title 15A - Environmental and Natural Resources, Subchapter 2B-Surface water and wetland standards, Rule 0211-Fresh surface water quality standards for class C waters (Class C is defined as freshwaters protected for secondary recreation, fishing, aquatic life including propagation and survival, and wildlife). Section 3(a) of Rule 0211 applies to all fresh surface waters and states that chlorophyll a is not to exceed 40 ug/L.
Guideline Reference: North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
  North Carolina standards, criteria, or toxic concentrations. Adopted per title 15A North Carolina Administrative Code subchapter 2B - Surface water and wetland standards
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 1/12/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
26819
Region 3     
Oso Flaco Lake
 
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 the sample size is insufficient to determine with the power and confidence of the Listing Policy if water quality standards are being met.
 
State Board Staff 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 26819, Chlorpyrifos
Region 3     
Oso Flaco Lake
 
LOE ID: 16297
 
Pollutant: Chlorpyrifos
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (04SW3001) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Chlorpyrifos.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion 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
  Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: One hour average maximum concentration 0.025 ug/L as stated in Sipmann and 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: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected on a single day 2/28/2007. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
26872
Region 3     
Oso Flaco Lake
 
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 the sample size is insufficient to determine with the power and confidence of the Listing Policy if water quality standards are being met.
 
State Board Staff 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 26872, Diazinon
Region 3     
Oso Flaco Lake
 
LOE ID: 16720
 
Pollutant: Diazinon
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (04SW3001) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Diazinon.
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion 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
  Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: One hour average maximum concentration 0.16 ug/L as stated in Sipmann and 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: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected on a single day 2/28/2007. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
26709
Region 3     
Oso Flaco Lake
 
Pollutant: Fecal Coliform
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 26709, Fecal Coliform
Region 3     
Oso Flaco Lake
 
LOE ID: 11603
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 2000/100 ml, nor shall more than ten percent of samples collected during any 30-day period exceed 4000/100 ml.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 1/12/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 26709, Fecal Coliform
Region 3     
Oso Flaco Lake
 
LOE ID: 11602
 
Pollutant: Fecal Coliform
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 15
Number of Exceedances: 2
 
Data and Information Type: PATHOGEN MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 2 of 15 samples exceed the criterion for Coliform, Fecal.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: Fecal coliform concentration, based on a minimum of not less than five samples for any 30-day period, shall not exceed a log mean of 200 MPN/100 ml, nor shall more than ten percent of total samples during any 30-day period exceed 400 MPN/100 ml.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 1/12/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
29786
Region 3     
Oso Flaco Lake
 
Pollutant: Low Dissolved Oxygen
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 29786, Low Dissolved Oxygen
Region 3     
Oso Flaco Lake
 
LOE ID: 13446
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 6/27/2000-9/6/2000. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 29786, Low Dissolved Oxygen
Region 3     
Oso Flaco Lake
 
LOE ID: 13443
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 15 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 2/3/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 29786, Low Dissolved Oxygen
Region 3     
Oso Flaco Lake
 
LOE ID: 13444
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 15
Number of Exceedances: 4
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 4 of 15 samples exceed the criterion for Oxygen, Saturation.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: Median values should not fall below 85% saturation as a result of controllable water quality conditions.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 2/3/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 29786, Low Dissolved Oxygen
Region 3     
Oso Flaco Lake
 
LOE ID: 13464
 
Pollutant: Oxygen, Dissolved
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Dissolved
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed RWQCB3 - Central Coast Ambient Monitoring Program (Lakes) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Oxygen, Dissolved.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, dissolved oxygen concentration shall not be reduced below 5.0 mg/l at any time.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 2 monitoring sites: 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, and 312OFL2b-Oso Flaco Lake Boardwalk at second alcove. At each of the two locations, three different depth samples were collected consistent with section 6.1.5.6 of the Listing policy, the lowest Dissolved Oxygen measurement at each location was used for this assessment.
Temporal Representation: Data was collected on two consecutive dates 9/7/2000-9/8/2000.
Environmental Conditions: Oso Flaco Lake is no more than 4 feet deep at the two monitoring locations however temperature, salinity, dissolved oxygen and pH gradients were observed on the two sample dates.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 29786, Low Dissolved Oxygen
Region 3     
Oso Flaco Lake
 
LOE ID: 13465
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Data for this line of evidence for Oso Flaco Lake was collected at 2 monitoring sites: 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, and 312OFL2b-Oso Flaco Lake Boardwalk at second alcove. At each of the two locations, three different depth samples were collected consistent with section 6.1.5.6 of the Listing policy, the lowest Oxygen Saturation measurement at each location was used for this assessment.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: Median values should not fall below 85% saturation as a result of controllable water quality conditions.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 6 monitoring sites [ 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, 312OFL2b-Oso Flaco Lake Boardwalk at second alcove, 312OFL2b-Oso Flaco Lake Boardwalk at second alcove, 312OFL2b-Oso Flaco Lake Boardwalk at second alcove]
Temporal Representation: Data was collected on two consecutive dates 9/7/2000-9/8/2000.
Environmental Conditions: Oso Flaco Lake is no more than 4 feet deep at the two monitoring locations however temperature, salinity, dissolved oxygen and pH gradients were observed on the two sample dates.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 29786, Low Dissolved Oxygen
Region 3     
Oso Flaco Lake
 
LOE ID: 13462
 
Pollutant: Dissolved oxygen saturation
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 2
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 1 of 2 samples exceed the criterion for Oxygen, Saturation.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: Median values should not fall below 85% saturation as a result of controllable water quality conditions.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 6/27/2000-9/6/2000. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
27141
Region 3     
Oso Flaco Lake
 
Pollutant: Turbidity
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 27141, Turbidity
Region 3     
Oso Flaco Lake
 
LOE ID: 13445
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 8
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 2 of 8 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 4/10/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 27141, Turbidity
Region 3     
Oso Flaco Lake
 
LOE ID: 13463
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 6/27/2000-9/6/2000. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 27141, Turbidity
Region 3     
Oso Flaco Lake
 
LOE ID: 13466
 
Pollutant: Turbidity
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed RWQCB3 - Central Coast Ambient Monitoring Program (Lakes) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 3 samples exceed the criterion for Turbidity(NTU).
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Waters shall be free of changes in turbidity that cause nuisance or adversely affect beneficial uses. Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Sigler et al. (1984) states that turbidities of 25 NTU's or greater caused reduction in juvenile salmonid growth due to interference with their ability to find food.
Guideline Reference: Effects of chronic turbidity on density and growth of steelheads and coho salmon. Transactions of the American Fisheries Society 113:142-150
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 2 monitoring sites: 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, and 312OFL2b-Oso Flaco Lake Boardwalk at second alcove. At each of the two locations, three different depth samples were collected consistent with section 6.1.5.6 of the Listing policy, the average turbidity measurement at each location was used for this assessment.
Temporal Representation: Data was collected on two consecutive dates 9/7/2000-9/8/2000.
Environmental Conditions: Oso Flaco Lake is no more than 4 feet deep at the two monitoring locations however temperature, salinity, dissolved oxygen and pH gradients were observed on the two sample dates.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
27529
Region 3     
Oso Flaco Lake
 
Pollutant: Unknown Toxicity
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 it cannot be determined if applicable water quality standards are not being exceeded because sample count is insufficient.
 
State Board Staff 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 27529, Unknown Toxicity
Region 3     
Oso Flaco Lake
 
LOE ID: 23947
 
Pollutant: Invertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (04SW3001) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Ceriodaphnia dubia Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: 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)
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected on a single day 2/28/2007. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 27529, Unknown Toxicity
Region 3     
Oso Flaco Lake
 
LOE ID: 24627
 
Pollutant: Plant Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 1
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (04SW3001) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 1 of 1 samples exceed the criterion for Toxicity, Selenastrum capricornutum Growth (Cell Density) 4 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction in cell count of test organism relative to the control (alpha < 0.05) and cell count <80% of control.
Guideline Reference: 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)
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected on a single day 2/28/2007. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 27529, Unknown Toxicity
Region 3     
Oso Flaco Lake
 
LOE ID: 23955
 
Pollutant: Vertebrate Toxicity
LOE Subgroup: Toxicity
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 1
Number of Exceedances: 0
 
Data and Information Type: TOXICITY TESTING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP_SWAMP Monitoring (04SW3001) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 1 samples exceed the criterion for Toxicity, Pimephales promelas Survival (%) 7 days. Toxicity is defined by SWAMP (2004) as follows: Significant toxicity in the survival endpoint when compared to the negative control based on a statistical test with alpha of less than 5%, and less than the evaluation threshold (both criteria are met).
Data Reference: Final Data File used for assessment: SWAMP Toxicity Data 2001-06
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: All waters shall be maintained free of toxic substances in concentrations which are toxic to, or which produce detrimental physiological responses in, human, plant, animal, or aquatic life. Compliance with this objective will be determined by use of indicator organisms, analyses of species diversity, population density, growth anomalies, toxicity bioassays of appropriate duration, or other appropriate methods as specified by the Regional Board (Water Quality Control Plan, Central Coast Basin, Chapter III, Section II.A.2 Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries).
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline: Significant reduction of survival of test organism relative to the control (alpha < 0.05) and test organism survival is 20% less than the control survival.
Guideline Reference: 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)
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected on a single day 2/28/2007. SWAMP toxicity monitoring includes both water samples (collected in both winter and summer) and sediment samples (collected in spring).
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
30166
Region 3     
Oso Flaco Lake
 
Pollutant: pH
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)(2010)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
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 Staff 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 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11604
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 1 of 13 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 2/3/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11625
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed RWQCB3 - Central Coast Ambient Monitoring Program (Lakes) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 2 of 3 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 2 monitoring sites: 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, and 312OFL2b-Oso Flaco Lake Boardwalk at second alcove. At each of the two locations, three different depth samples were collected consistent with section 6.1.5.6 of the Listing policy, the highest pH measurement at each location was used for this assessment.
Temporal Representation: Data was collected on two consecutive dates 9/7/2000-9/8/2000.
Environmental Conditions: Oso Flaco Lake is no more than 4 feet deep at the two monitoring locations however temperature, salinity, dissolved oxygen and pH gradients were observed on the two sample dates.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11624
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed RWQCB3 - Central Coast Ambient Monitoring Program (Lakes) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 2 of 3 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 2 monitoring sites: 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, and 312OFL2b-Oso Flaco Lake Boardwalk at second alcove. At each of the two locations, three different depth samples were collected consistent with section 6.1.5.6 of the Listing policy, the highest pH measurement at each location was used for this assessment.
Temporal Representation: Data was collected on two consecutive dates 9/7/2000-9/8/2000.
Environmental Conditions: Oso Flaco Lake is no more than 4 feet deep at the two monitoring locations however temperature, salinity, dissolved oxygen and pH gradients were observed on the two sample dates.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11623
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life 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: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 6/27/2000-9/6/2000. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11621
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Water Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for water contact recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 6/27/2000-9/6/2000. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11606
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 13
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 13 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 2/3/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11622
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 2
Number of Exceedances: 0
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Diurnal Dissolved Oxygen Sampling (DO) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 0 of 2 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 6/27/2000-9/6/2000. Diurnal monitoring conducted in summer months at all CCAMP monitoring sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11605
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Non-Contact Recreation
 
Number of Samples: 13
Number of Exceedances: 1
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed CCAMP Santa Maria (SantaMaria) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 1 of 13 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: The Water Quality Control Plan, Central Coast Basin objective for non-contact water recreation uses (Section II.A.2. Objectives for All Inland Surface Waters, Enclosed Bays, and Estuaries, II.A.2.a) states the following: pH value shall neither be depressed below 6.5 nor raised above 8.3.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 1 monitoring site [ 312OFL-Oso Flaco Lake at culvert]
Temporal Representation: Data was collected over the time period 2/3/2000-3/1/2001. Santa Maria watershed is one of five annual rotation areas that are monitored for conventional pollutants by CCAMP staff monthly for one year. Toxicity monitoring is conducted twice during the rotation year (winter and summer) at a subset of sites.
Environmental Conditions: Staff is not aware of any special conditions that might effect interpretation of the data.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
Line of Evidence (LOE) for Decision ID 30166, pH
Region 3     
Oso Flaco Lake
 
LOE ID: 11640
 
Pollutant: pH
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: None
 
Beneficial Use: Warm Freshwater Habitat
Aquatic Life Use: Warm Freshwater Habitat
 
Number of Samples: 3
Number of Exceedances: 2
 
Data and Information Type: PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: Central Coast Regional Board Staff assessed RWQCB3 - Central Coast Ambient Monitoring Program (Lakes) data for Oso Flaco Lake to determine beneficial use support and results are as follows: 2 of 3 samples exceed the criterion for pH.
Data Reference: Final Data File used for assessment: CCAMP Water Quality Data_file1
  Final Data File used for assessment: CCAMP Water Quality Data_file2
  Final Data File used for assessment: CCAMP Water Quality Data_file3
 
SWAMP Data: SWAMP
 
Water Quality Objective/Criterion: Water Quality Control Plan, Central Coast Basin, General Objective, Chapter III, Section II.A.2 General Objectives for all Inland Surface Waters, Enclosed Bays and Estuaries states the following: For waters not mentioned by a specific beneficial use, the pH value shall not be depressed below 7.0 or raised above 8.5.
Objective/Criterion Reference: Water Quality Control Plan (Basin Plan) - Central Coast Region (Region 3)
 
Evaluation Guideline:
Guideline Reference:
 
Spatial Representation: Data for this line of evidence for Oso Flaco Lake was collected at 2 monitoring sites: 312OFL1b-Oso Flaco Lake Boardwalk at first alcove, and 312OFL2b-Oso Flaco Lake Boardwalk at second alcove. At each of the two locations, three different depth samples were collected consistent with section 6.1.5.6 of the Listing policy, the highest pH measurement at each location was used for this assessment.
Temporal Representation: Data was collected on two consecutive dates 9/7/2000-9/8/2000.
Environmental Conditions: Oso Flaco Lake is no more than 4 feet deep at the two monitoring locations however temperature, salinity, dissolved oxygen and pH gradients were observed on the two sample dates.
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. All data are flagged as appropriate.
QAPP Information Reference(s):
 
 
DECISION ID
18938
Region 3     
Oso Flaco Lake
 
Pollutant: Dieldrin
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)(2010)
Revision Status Original
Sources: Source Unknown
Expected TMDL Completion Date: 2013
Impairment from Pollutant or Pollution: Pollutant
 
Regional Board Conclusion: Region 3 data was not included in the 2012 Integrated Report so all decisions are carried over from the 2010 listing cycle.
 
Regional Board Decision Recommendation: No new data were assessed for 2012. The decision has not changed.
 
State Board Staff 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 be placed on the section 303(d) list because applicable water quality standards are exceeded and a pollutant contributes to or causes the problem.
 
 
Line of Evidence (LOE) for Decision ID 18938, Dieldrin
Region 3     
Oso Flaco Lake
 
LOE ID: 700
 
Pollutant: Dieldrin
LOE Subgroup: Pollutant-Tissue
Matrix: Tissue
Fraction: Total
 
Beneficial Use: Commercial or recreational collection of fish, shellfish, or organisms
 
Number of Samples: 3
Number of Exceedances: 3
 
Data and Information Type: Fish tissue analysis
Data Used to Assess Water Quality: Three out of 3 samples exceeded (TSMP, 2002). A total of 2 filet composite samples of bluegill and one filet composite of hitch were collected. Bluegill were collected from 1993. Hitch were collected 2001. The guideline was exceeded in all samples.
Data Reference: Placeholder reference 2006 303(d)
 
SWAMP Data: Non-SWAMP
 
Water Quality Objective/Criterion: Central Coast RWQCB Basin Plan: No individual pesticide or combination of pesticides shall reach concentrations that adversely affect beneficial uses. There shall be no increase in pesticide concentrations found in bottom sediments or aquatic life.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
 
Evaluation Guideline: 2 ng/g (OEHHA Screening Value) (Brodberg & Pollock, 1999).
Guideline Reference: Placeholder reference 2006 303(d)
 
Spatial Representation: One station located in lake at foot of Oso Flaco Road.
Temporal Representation: Samples were collected 1993 and 2001.
Environmental Conditions:
QAPP Information: Toxic Substances Monitoring Program 1992-93 Data Report.
Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 2001-2002. Department of Fish and Game.
QAPP Information Reference(s):