# Draft 2008 California 303(d)/305(b) Integrated Report

# Supporting Information

## Regional Board 5 - Central Valley Region

Water Body Name: | Arcade Creek
Water Body ID: | CAR5192100019980813113546
Water Body Type: | River & Stream

DECISION ID | 6503
Pollutant: | Copper
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)(2006)
Revision Status | Revised
Sources: | Source Unknown
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for removal from the section 303(d) list under section 4.1 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess pollutant. Six samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of 17 samples exceeded the calculated CTR CCC values and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: | N/A
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 6503

LOE ID: | 25295
Pollutant: | Copper, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 17
Number of Exceedances: | 6
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | City of Sacramento Stormwater urban tributary data. Six of 17 4-day average concentrations exceeded the calculated CTR CCC criterion values, and 5 of 21 1-hour maximum concentrations exceeded the calculated CTR CMC citerion values.
Data Reference:
Water Quality Objective/Criterion: | Calculated CTR 4-day average CCC, and calculated CTR 1-hour maximum hardness-dependent criteria.
Objective/Criterion Reference:
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Water samples were collected from Arcade Creek at Watt Avenue.
Temporal Representation: | Water samples were collected from Arcade Creek approximately daily to semi-annualy between 14 December 2003 and 3 April 2007.
Environmental Conditions: |
QAPP Information: | Good.
QAPP Information Reference(s):
LOE ID: | 4285
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
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)
Water Quality Objective/Criterion: |
Objective/Criterion Reference: | Placeholder reference pre-2006 303(d)
Evaluation Guideline: |
Guideline Reference: | Placeholder reference pre-2006 303(d)
Spatial Representation: | Unspecified
Temporal Representation: | Unspecified
Environmental Conditions: | Unspecified
QAPP Information: | Unspecified
QAPP Information Reference(s):

DECISION ID | 4475
Pollutant: | Chlorpyrifos
Final Listing Decision: | Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (being addressed by USEPA approved TMDL)(2006)
Revision Status | Revised
Sources: | Urban Runoff/Storm Sewers
TMDL Name: | Sacramento Area Urban Creeks TMDLs
TMDL Project Code: | 194
Date TMDL Approved by USEPA: | 11/30/2004
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for removal from the section 303(d) list under sections 2.2 and 4.1 of the Listing Policy. Under section 4.1 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 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. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Six of 81 samples exceeded the CDFG 1-hour average criterion (25 ng/L) more than once every three years (pursuant to Section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met). A Sacramento Urban Creeks TMDL was approved by the RWQCB in 2004 and subsequently approved by USEPA in 2004 and is expected to result in attainment of the standard.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 4475

LOE ID: | 21619
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 11
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Water samples were collected on 27 dates and analyzed for chlorpyrifos. Zero samples contained reportable levels of chlorpyrifos, but the reporting limits for 16 of the samples were greater than the 1-hour average criterion of 0.025 ug/L. The reporting levels for 11 of the samples were lower than the 4-day average criterion of 0.015 ug/L.
Data Reference: | Final Proposition 50 Grant Monitoring Report, 2005 - 2007. Includes Quality Assurance Project Plan (QAPP) Revision 1.2.0, Appendix A, March 2006
| Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003
| Quality Assurance Project Plans prepared for Sacramento River Watershed Program
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment chlorpyrifos criteria for freshwater aquatic life protection: 0.015 ug/L 4-day average, and 0.025 ug/L 1-hour avergae, not to exceed more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from Arcade Creek at Watt Avenue.
Temporal Representation: | Samples were collected 27 times at intervals ranging from daily to semiannually, between December 2003 and April 2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with Central Valley Water Board Monitoring and Reporting Program (order number R5-2002-0206) requirements.
QAPP Information Reference(s):
LOE ID: | 21618
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 4
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Ten water samples were collected from Arcade Creek between January and April 2003, representing eight calculated 4-day average concentrations and ten 1-hour average concentrations. Five of the ten sample results did not meet the laboratory acceptance criteria and were, therefore, not included in this analysis. Two of the four usable calculated 4-day average concentrations exceeded the 4-day average criterion of 0.015 ug/L. Zero of the 5 usable 1-hour average concentrations exceeded 1-hour average criterion of 0.025 ug/L.
Data Reference: | Concentrations of pesticides in Sacramento metropolitan area rainwater and creeks during the 2001, 2002, 2003 orchard dormant spray season. Rancho Cordova, CA: Central Valley RWQCB
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment chlorpyrifos criteria for freshwater aquatic life protection: 0.015 ug/L 4-day average, and 0.025 ug/L 1-hour average, not to exceed more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from Arcade Creek at Watt Avenue.
Temporal Representation: | Ten water samples were collected from Arcade Creek between 23 January 2003 and 24 April 2003, at intervals ranging from approximately twice-weekly to every three weeks.
Environmental Conditions: |
QAPP Information: | Data quality: Good.
QAPP Information Reference(s):
LOE ID: | 21620
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Twenty-seven water samples were collected from Arcade Creek between June 1999 and May 2002, representing 27 potential 4-day average concentrations and 27 potential 1-hour average concentrations. All 27 water samples had a method detection limit (0.05 ug/L) which is higher than both the 4-day average criterion of 0.015 ug/L and the 1-hour average criterion of 0.025 ug/L. Therefore, the 27 samples were not included in this analysis, and 0 of 0 available 4-day average concentrations and 0 of 0 1-hour average concentrations exceeded the criteria.
Data Reference: | Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment chlorpyrifos criteria for freshwater aquatic life protection: 0.015 ug/L 4-day average, and 0.025 ug/L 1-hour average, not to be exceeded more than once every three years.
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from Arcade Creek at Norwood Avenue.
Temporal Representation: | Samples were collected monthly between June 1999 and May 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program.
QAPP Information Reference(s):
LOE ID: | 21621
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 56
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Eighty water samples were collected from Arcade Creek from January 2001 through September 2005, representing fifty-six calculated 4-day average concentrations and fifty-six 1-hour average concentrations. Two of the 56 samples had calculated 4-day average concentrations that exceeded the 4-day average criterion of 0.015 ug/L. Zero of the 56 samples exceeded the 1-hour average criterion of 0.025 ug/L. Twenty-four additional water samples had method detection limits (0.02 to 0.05 ug/L) that are higher than the 4-day average criterion (0.015 ug/L) and, therefore, these 24 sample results were not included in this analysis.
Data Reference: | Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
| Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
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
| Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment chlorpyrifos criteria for freshwater aquatic life protection: 0.015 ug/L 4-day average, and 0.025 ug/L 1-hour average, not to be exceeded more than once every three years .
Guideline Reference: | Water quality criteria for diazinon and chlorpyrifos. Administrative Report 00-3. Rancho Cordova, CA: Pesticide Investigations Unit, Office of Spills and Response. CA Department of Fish and Game
Spatial Representation: | Samples were collected from Arcade Creek at Norwood Avenue, and near the Del Paso Heights, California USGS NAWQA site.
Temporal Representation: | Samples were collected at variable intervals (e.g. biweekly, monthly) from January 2001 through September 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides
LOE ID: | 2645
Pollutant: | Chlorpyrifos
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 10
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Chlorpyrifos was detected 40 percent of the time at levels above the CDFG aquatic life water quality criterion for chlorpyrifos - 0.020 ug/L (Spector et al., 2004). Ten samples were collected in 2003 in Arcade Creek at Watt Ave.; two exceeded the CDFG 4-day average.
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | The narrative pesticide objectives state, in part: - No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses, - Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses, - Pesticide concentrations shall not exceed those allowable by applicable antidegradation policies, and - Pesticide concentrations shall not exceed the lowest levels technically and economically achievable. The Basin Plans narrative water quality objective for toxicity states that, '...all waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.'
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: | CDFG Hazard Assessment Criteria - 14 ng/L 4-day average.
Guideline Reference: | Placeholder reference 2006 303(d)
Spatial Representation: | The Arcade Creek surface water-sampling site (C1) is located at Watt Avenue; near the USGS Arcade Creek near Del Paso Heights flow gauge. Rainwater samples were collected at Arcade Creek at Greenback Lane. Samples were collected beneath the water surface as near as possible to the center of the stream when water levels were low or when access was only possible from the bank. Otherwise, three to four grab samples were collected as one integrated grab sample.
Temporal Representation: | Storm events were sampled during the orchard dormant spray season months of January and February 2001 and 2002, and January through April 2003, to determine pesticide concentrations in rain and creeks during and after the orchard dormant spray season.
Environmental Conditions: | Typical dry weather flows in Arcade Creek are less than 1 cubic foot per second (cfs), but, during rainfall events, storm runoff into Arcade Creek can create flows of over 2,200 cfs, as measured at the USGS gage station located at Watt Avenue.
QAPP Information: | San Joaquin River TMDL Quality Assurance Project Plan.
QAPP Information Reference(s):

DECISION ID | 4476
Pollutant: | Diazinon
Final Listing Decision: | Do Not Delist from 303(d) list (being addressed with USEPA approved TMDL)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (being addressed by USEPA approved TMDL)(2006)
Revision Status | Revised
Sources: | Agriculture | Urban Runoff/Storm Sewers
TMDL Name: | Sacramento Area Urban Creeks TMDLs
TMDL Project Code: | 194
Date TMDL Approved by USEPA: | 11/30/2004
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for removal from the section 303(d) list under sections 2.2, 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. Four lines of evidence are available in the administrative record to assess this pollutant. Based on section 4.6, the waterbody has significant pesticide toxicity and the pollutant concentration exceeds the pesticide water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One hundred-two of 168 samples exceeded the CDFG 4-day average criterion for freshwater aquatic life protection, and this exceeds the allowable refquency listed in Table 4.1 of the Liasting Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met. A Sacramento Urban Creeks TMDLs was approved by the RWQCB in 2004 and subsequently approved by USEPA in 2004 and is expected to result in attainment of the standard.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: | After review of the available data and information for this recommendation, SWRCB staff conclude that the water body should be placed in the Water Quality Limited Segments Being Addressed category of the section 303(d) list because a TMDL has been approved by USEPA and an implementation plan has been approved.
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 4476

LOE ID: | 21583
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 4
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Twelve water samples were collected from Arcade Creek between February 2002 and February 2007, representing twelve calculated 4-day average concentrations and twelve 1-hour average concentrations. Three of the twelve calculated four-day average concentrations exceeded the 4-day average concentration criterion of 0.100 ug/L. Four of twelve 1-hour average concentrations exceeded the 1-hour average concentration of 0.160 ug/L.
Data Reference: | Evaluation of Additional Pesticide Monitoring Data - 2007 Update
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Fish and Game Hazard Assessment diazinon criteria for freshwater aquatic life protection: 0.160 ug/L 1-hour average concentration, and 0.100 ug/L 4-day average concentration not to be exceeded more than once every three years.
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
| Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation: | Samples were collected at Arcade Creek at Watt Avenue. Arcade Creek is a urban creek located in the greater Sacramento area.
Temporal Representation: | Samples were collected on 02/02/2004, 02/18/2004, 04/13/2004, 10/06/2004, 01/28/2005, 02/15/2005, 04/12/2005, 02/07/2006, 02/27/2006, 03/06/2006, 12/08/2006, and 02/09/2007.
Environmental Conditions: |
QAPP Information: | Data quality: Good. Monitoring was conducted in accordance with the Sacramento Municipal Storm Water Permitting Program and Central Valley Water Board Monitoring and Reporting Program (order number R5-2002-0206) requirements (CVRWQCB, 2002).
QAPP Information Reference(s):
LOE ID: | 2647
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 10
Number of Exceedances: | 3
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Ninety percent of the time during the 2001-2002 sampling period, diazinon concentrations at the Arcade Creek site were greater than the CDFG aquatic life water quality criterion for diazinon. In 2003, 10 samples were taken; 3 exceeded the CDFG criteria (Spector et al., 2004).
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | The narrative pesticide objectives state, in part: - No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses, - Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses, - Pesticide concentrations shall not exceed those allowable by applicable antidegradation policies, and - Pesticide concentrations shall not exceed the lowest levels technically and economically achievable. The Basin Plans narrative water quality objective for toxicity states that 'all waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life'.
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: | CDFG Hazard Assessment Criteria 0.16 ug/L 1-hour average (Siepman & Finlayson, 2000; Finlayson, 2004).
Guideline Reference: | Placeholder reference 2006 303(d)
Spatial Representation: | The Arcade Creek surface water-sampling site (C1) is located at Watt Avenue, near the USGS Arcade Creek near Del Paso Heights flow gauge. Rainwater samples were collected at Arcade Creek at Greenback Lane. Samples were collected beneath the water surface as near as possible to the center of the stream when water levels were low or when access was only possible from the bank. Otherwise, three to four grab samples were collected as one integrated grab sample.
Temporal Representation: | Storm events were sampled during the orchard dormant spray season months of January and February 2001 and 2002, and January through April 2003, to determine pesticide concentrations in rain and creeks during and after the orchard dormant spray season.
Environmental Conditions: | Typical dry weather flows in Arcade Creek are less than 1 cubic foot per second (cfs), but, during rainfall events, storm runoff into Arcade Creek can create flows of over 2,200 cfs, as measured at the USGS gage station located at Watt Avenue.
QAPP Information: | San Joaquin River TMDL Quality Assurance Project Plan.
QAPP Information Reference(s):
LOE ID: | 2648
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 87
Number of Exceedances: | 68
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Analysis methods used includes ELISA, GC, Gas or Liquid chromatograph in the EPA 8140 scan, EPA 8141A, GC/MS. All 22 samples at Del Paso Heights exceeded the CDFG 4-day average and 1-hour average. Out of 65 samples taken at Norwood Avenue, 46 exceeded the CDFG 1-hour average and 2 exceeded the 4 day average (USGS, 2005).
Data Reference: | Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: | Pesticide concentrations shall not exceed those allowable by applicable antidegradation policies (see State Water Resources Control Board Resolution No. 68-16 and 40 C.F.R. Section 131.12). Pesticide concentrations shall not exceed the lowest levels technically and economically achievable. A trend in declining water quality has not been established per the Policy in section 3.1.10. No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. Discharges shall not result in pesticide concentrations in bottom sediments or aquatic life that adversely affect beneficial uses. Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the executive Officer. Waters designated for use as domestic or municipal supply (MUN) shall not contain concentrations of pesticides in excess of the Maximum Contaminant Levels set forth in California Code of Regulations, Title 22, Division 4, Chapter 15.
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: | Diazinon - CDFG Hazard Assessment Criteria - 0.10 ug/L 4-day average and 0.16 ug/L 1-hour average (Siepman & Finlayson, 2000; Finlayson, 2004).
Guideline Reference: | Placeholder reference 2006 303(d)
Spatial Representation: | Samples were taken at Arcade Creek at Norwood Ave and near Del Paso Heights.
Temporal Representation: | Samples for the Del Paso Heights were taken in 1996 (2x); 1997 (2/month for the year); and 1998 (1/month for the first 4 months). Samples at the Norwood Ave. site were taken in 1996 (2); 1997 (1/month 1-6); 1998-99 (1/month x 12); 2000 (2/12 months); 2001(7 samples) and 2002 (3 samples).
Environmental Conditions: |
QAPP Information: | Data from USGS reports are considered of adequate quality per section 6.1.4 of the Policy.
QAPP Information Reference(s):
LOE ID: | 21584
Pollutant: | Diazinon
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 59
Number of Exceedances: | 27
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fifty-nine water samples were collected between January 2001 and September 2005, representing fifty-nine calculated 4-day average concentrations and fifty-nine 1-hour average concentrations. Twenty-seven of the fifty-nine calculated 4-day average concentrations exceeded the 4-day average criterion of 0.100 ug/L. Nineteen of the fifty-nine 1-hour average concentrations exceeded the 1-hour average criterion of 0.160 ug/L.
Data Reference: | National Water Quality Assessment database, Sacramento Study Unit data
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Fish and Game Hazard Assessment diazinon criteria for freshwater aquatic life protection: 0.160 ug/L 1-hour average, and 0.100 ug/L 4-day average concentration, not to be exceeded more than once every three years.
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
| Water quality for diazinon. Memorandum to J. Karkoski, Central Valley RWQCB. Rancho Cordova, CA: Pesticide Investigation Unit, CA Department of Fish and Game
Spatial Representation: | Samples were collected from Arcade Creek near Del Paso Heights. Arcade Creek is an urban creek in the greater Sacramentop area.
Temporal Representation: | Samples were collected approximately monthly from January 2001 to September 2004, and apparoximately bi-monthly from October 2004 to September 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):

DECISION ID | 12840
Pollutant: | Bis(2ethylhexyl)phthalate (DEHP)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Two of the four samples exceeded the California Toxics Rule water quality limits for human health, consumption of water and aquatic organisms (1.8 µg/L). Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The available data do not meet the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Two of four samples exceed the water quality objective listed in the California Toxics Rule and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. These data were estimated concentrations, therefore it cannot be determined if standards were exceeded. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 12840

LOE ID: | 25652
Pollutant: | Bis(2ethylhexyl)phthalate (DEHP)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 4
Number of Exceedances: | 2
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Four samples were taken from Arcade Creek between December 2003 and October 2006. Two of the 4 samples exceeded the California Toxics Rule criterion of 1.8 ug/L. The samples that exceeded the standard were collected on 19 October 2004 and 5 October 2006. The data used for this assessment were monitoring data submitted as required by the Waste Discharge Requirements for County of Sacramento and Cities of Citrus Heights, Elk Grove, Folsom, Galt, and Sacramento Storm Water Discharges from Municipal Separate Storm Sewer Systems, Sacramento County (NPDES # CAS082597). Sacramento Stormwater Urban Tributaries.
Data Reference: | Evaluation of Additional Pesticide Monitoring Data - 2007 Update
Water Quality Objective/Criterion: | The California Toxics Rule criterion for Bis(2-ethylhexyl)phthalate, based on Human Health Protection (30-day avergae) for carcinogenicity at the 1-in-a-million risk level, for sources of drinking water based on water and fish consumption is 1.8 ug/L.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Spatial Representation: | Water samples were collected from Arcade Creek at Watt Avenue, in Sacramento County.
Temporal Representation: | Water samples were collected on 14 December 2003, 19 October 2004, 1 December 2005, and 5 October 2006.
Environmental Conditions: |
QAPP Information: | Monitoring was conducted in accordance the Monitoring and Reporting Program Requirements stipulated in Order No. R5-2002-0206 (NPDES No. CAS082597) (CVRWQCB 2002).
QAPP Information Reference(s):

DECISION ID | 13908
Pollutant: | Carbaryl
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. Zero of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 23 calculated 4-day average carbaryl concentrations exceeded the 4-day average criterion representing the narrative toxicity objective, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Zero of 26 1-hour average carbaryl concentrations exceeded the 1-hour average criterion representing the narrative toxicity objective, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 5. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that though this water body is impaired for sediment toxicity, these water body-pollutant combinations should not be placed on the section 303(d) list because applicable water quality standards for these pollutants are not being exceeded
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 13908

LOE ID: | 26053
Pollutant: | Carbaryl
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 4
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Four water samples were collected from Arcade Creek annually, from December 2003 to October 2006. Water samples were collected from Arcade Creek under the City of Sacramento's urban tributary stormwater permit. The four water samples represent four calculated 4-day average concentrations and four 1-hour average concentrations. Zero of the four calculated 4 available 4-day average concentrations exceeded the 4-day maximum concentration guideline of 2.53 ug/L. Zero of the four 1-hour average concentrations exceeded the 1-hour average criterion of 2.53 ug/L.
Data Reference: | Sacramento stormwater urban tributary NPDES permit monitoring data, 2003 to 2007
| Evaluation of Additional Pesticide Monitoring Data - 2007 Update
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment carbaryl criteria for freshwater aquatic life protection: 2.53 ug/L for both 4-day average and 1-hour average concentrations (Siepmann and Jones, 1998).
Guideline Reference: | Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game
Spatial Representation: | Water samples were collected from Arcade Creek at Watt Avenue.
Temporal Representation: | Water samples were collected from Arcade Creek annually, on: 14 December 2003, 19 October 2004, December 1 2005, and 5 October 2006.
Environmental Conditions: |
QAPP Information: | Data Quality: Good. Samples collected under Sacramento County's NPDES Stormwater permit.
QAPP Information Reference(s):
LOE ID: | 25813
Pollutant: | Carbaryl
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 8
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Ten water samples were collected from Arcade Creek between January and April 2003, representing eight calculated 4-day average concentrations and ten 1-hour maximum concentrations. The samples were collected under the Sacramento urban creeks pesticide TMDL program. Zero of eight calculated 4-day average concentrations exceeded the 4-day average criterion of 2.53 ug/L. Zero of ten 1-hour maximum concentrations exceeded the 1-hour maximum criterion of 2.53 ug/L.
Data Reference: | Concentrations of pesticides in Sacramento metropolitan area rainwater and creeks during the 2001, 2002, 2003 orchard dormant spray season. Rancho Cordova, CA: Central Valley RWQCB
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment Criteria: 2.53 ug/L for both 4-day average and 1-hour maximum concentrations (Siepmann and Jones, 1998).
Guideline Reference: | Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game
Spatial Representation: | Water samples were collected from Arcade Creek at Watt Avenue.
Temporal Representation: | Samples were collected between January and April 2003 at irregular intervals ranging from twice weekly, weekly, and monthly.
Environmental Conditions: |
QAPP Information: | Data Quality: Good.
QAPP Information Reference(s): | Concentrations of pesticides in Sacramento metropolitan area rainwater and creeks during the 2001, 2002, 2003 orchard dormant spray season. Rancho Cordova, CA: Central Valley RWQCB
LOE ID: | 26067
Pollutant: | Carbaryl
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 6
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Six water samples were collected from Arcade Creek between November 1999 and September 2001 as part of the Sacramento River Watershed Program. The six water samples represent five calculated 4-day average concentrations and six 1-hour average concentrations. Zero of the five calculated 4-day average concentrations exceeded the 4-day average criterion of 2.53 ug/L. Zero of the six 1-hour average concentrations exceeded the 1-hour average criterion of 2.53 ug/L.
Data Reference: | Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment carbaryl criteria for freshwater aquatic life protection: 2.53 ug/L for both 4-day average and 1-hour average concentrations (Siepmann and Jones, 1998).
Guideline Reference: | Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game
Spatial Representation: | Water samples were collected from Arcade Creek at Norwood Avenue.
Temporal Representation: | Water samples were collected from Arcade Creek on 16 November 1999, 19 April 2000,16 May 2000, 9 April 2001, and 26 September 2001.
Environmental Conditions: |
QAPP Information: | Data Quality: Good.
QAPP Information Reference(s):
LOE ID: | 26066
Pollutant: | Carbaryl
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 6
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Six water samples were collected from Arcade Creek between October 2002 and June 2003, as part of the Sacramento River Watershed Program. The six water samples represent six calculated 4-day average concentrations and six 1-hour average concentrations. Zero of the six calculated 4-day average concentrations exceeded the 4-day average criterion of 2.53 ug/L. Zero of the six 1-hour average concentrations exceeded the 1-hour average criterion of 2.53 ug/L.
Data Reference: | Sacramento River Watershed Program Annual Reports for 1999-2000, 2000-2001, 2001-2002, 2002-2003, and 2003-2004; and BDAT data 1998-2003
| Quality Assurance Project Plans prepared for Sacramento River Watershed Program
| SRWP Year 6 (2004) toxicity and water chemistry data files
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | California Department of Fish and Game Hazard Assessment carbaryl criteria for freshwater aquatic life protection: 2.53 ug/L for both 4-day average and 1-hour average concentrations (Siepmann and Jones, 1998).
Guideline Reference: | Hazard Assessment of the Insecticide Carbaryl to Aquatic Organisms in the Sacramento-San Joaquin River System. State of California Department of Fish and Game
Spatial Representation: | Water samples were collected from Arcade Creek at Norwood Avenue.
Temporal Representation: | Water samples were collected from Arcade Creek on 25 and 26 October 2002, 3 March 2003, 11 April 2003, 5 and 12 May 2003, and 24 June 2003.
Environmental Conditions: |
QAPP Information: | Data Quality: Good.
QAPP Information Reference(s):

DECISION ID | 11240
Pollutant: | Diuron
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | (TYPE: 06SB DO NOT LIST_NON CONVENTIONAL POLL) This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. One of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 43 samples exceeded the toxicity objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11240

LOE ID: | 21602
Pollutant: | Diuron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 24
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Twenty-four water samples were collected bi-monthly from October 2004 through September 2005. Zero of 24 samples exceeded the maximum concentration of 1.3 ug/L.
Data Reference: | National Water Quality Assessment database, Sacramento Study Unit data
Water Quality Objective/Criterion: | Where valid testing has developed 96-hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The 96-hour EC50 for the most sensitive species to diuron exposure is 1.3 ug/L (ECOTOX, 2008).
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
Spatial Representation: | Samples were collected from Arcade Creek near Del Paso Heights. Arcade Creek is an urban creek in the greater Sacramento area.
Temporal Representation: | Samples were collected bimonthly from October 2004 to September 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):
LOE ID: | 21603
Pollutant: | Diuron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 19
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Twenty samples were collected from Arcade Creek at Norwood Avenue, from 2000 to 2002, representing 19 concentrations (two samples were taken in one day, and were subsequently counted as one sample). 1 of 19 concentrations exceeded the maximum concentration of 1.3 ug/L.
Data Reference: | Sacramento River watershed program (SRWP) water quality database. Davis, CA
Water Quality Objective/Criterion: | Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives (CVRWQCB, 2007).
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The 96- hour EC50 for the most sensitive species, Chlorella pyrenoidosa, is 1.3 ug/L.
Guideline Reference: | Ecotox database, http://cfpub.epa.gov/ecotox/
| Acute toxicity of 33 herbicides to the green alga Chlorella pyrenoidosa. Bulletin of Environmental Contamination and Toxicology. 66:536-541. Springer-Verlag New York Inc.
Spatial Representation: | Samples were collected from Arcade Creek at Norwood Avenue. Arcade Creek is an urban creek in the greater Sacramento area.
Temporal Representation: | Samples were collected approximately monthly from January 2000 through May 2002.
Environmental Conditions: |
QAPP Information: | Data quality: Excellent. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2000b, 2001b, 2002b, 2003b, 2006).
QAPP Information Reference(s):

DECISION ID | 11310
Pollutant: | Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of 35 samples exceeded the California Toxic Rule/USEPA (CTR/USEPA) criteria for human consumption of water and organisms with a 10-6 risk for carcinogens of 0.019 mg/g and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11310

LOE ID: | 21604
Pollutant: | Lindane/gamma Hexachlorocyclohexane (gamma-HCH)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 35
Number of Exceedances: | 1
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Thirty-five (35) water samples were collected from Arcade Creek from January 2001 through September 2004. One of the available thirty-five (35) samples exceeded the CTR criteria of 0.019 mg/g for human consumption of water and organisms.
Data Reference: | National Water Quality Assessment database, Sacramento Study Unit data
Water Quality Objective/Criterion: | - Sacramento/San Joaquin River Basin Plan for Pesticides: Total identifiable persistent chlorinated hydrocarbon pesticides shall not be present in the water column at concentrations detectable within the accuracy of analytical methods approved by the Environmental Protection Agency or the Executive Officer (CVRWQCB, 2007a). - California Toxics Rule Criteria (USEPA, 2000) based on criteria for human consumption of water and organisms with a 10-6 risk for carcinogens of 0.019 mg/g.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Samples were collected from Arcade Creek near Del Paso Heights in California. Arcade Creek is an urban creek in the greater Sacramento area.
Temporal Representation: | Samples were collected at monthly intervals between January 2001 and September 2004.
Environmental Conditions: |
QAPP Information: | Data quality: Good. In accordance with section 6.1.4 of the Listing Policy, data from major monitoring programs in California and Published USGS reports are considered of adequate quality.
QAPP Information Reference(s):

DECISION ID | 14250
Pollutant: | Pentachlorophenol (PCP)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 4 samples exceeded the CTR for pentachlorophenol of 0.28 ug/L, and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 14250

LOE ID: | 26072
Pollutant: | Pentachlorophenol (PCP)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 4
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Four water samples were collected from Arcade Creek between December 2003 and October 2006 for the City of Sacramento urban tributary stormwater permit. One of the 4 water samples contained pentachlorphenol at concentrations that exceeded the criterion of 0.28 ug/L.
Data Reference: | Sacramento stormwater urban tributary NPDES permit monitoring data, 2003 to 2007
| Evaluation of Additional Pesticide Monitoring Data - 2007 Update
Water Quality Objective/Criterion: | USEPA numeric criterion of 0.28 ug/L for human health protection (10-6 risk of carcinogens).
Objective/Criterion Reference: | Water Quality Standards 2000. Establishment of numeric criteria for priority toxic pollutants for the State of California: Rules and regulations. Federal Register Vol. 65, No. 97. Washington, D.C.: Environmental Protection Agency
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Water samples were collected from Arcade Creek at Watt Avenue.
Temporal Representation: | Water samples were collected yearly between December 2003 and June 2006.
Environmental Conditions: |
QAPP Information: | Data Quality: Unknown.
QAPP Information Reference(s):

DECISION ID | 14249
Pollutant: | Propanil (DCPA mono- and di-acid degrad)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of 55 water samples exceeded the Evaluation Guideline of 16 ug/L (based on a 5-day toxicity value using a freshwater diatom, Mavicula pelliculosa), and this does not exceed the narrative toxicity objective or the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff Recommendation: | After review of the available data and information, RWQCB staff concludes that though this water body is impaired for sediment toxicity, these water body-pollutant combinations should not be placed on the section 303(d) list because applicable water quality standards for these pollutants are not being exceeded
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 14249

LOE ID: | 26071
Pollutant: | Propanil (DCPA mono- and di-acid degrad)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 55
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Fifty-five water samples were collected from Arcade Creek between January 2001 and September 2005. Zero of the 55 water samples had propanil concentrations that exceeded the Evaluation Guideline value of 16 ug/L.
Data Reference: | Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
Water Quality Objective/Criterion: | Where valid testing has developed 96 hour LC50 values for aquatic organisms (the concentration that kills one half of the test organisms in 96 hours), the Board will consider one tenth of this value for the most sensitive species tested as the upper limit (daily maximum) for the protection of aquatic life. Other available technical information on the pesticide (such as Lowest Observed Effect Concentrations and No Observed Effect Levels), the water bodies and the organisms involved will be evaluated to determine if lower concentrations are required to meet the narrative objectives.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | The 5-day EC50 value, based on toxicity testing using a freshwater diatom (Navicula pelliculosa) is 16 ug/L.
Guideline Reference: | Ecotoxicity database. U.S. Environmental Protection Agency, Office of Pesticide Programs
Spatial Representation: | Water samples were collected from Arcade Creek at Norwood Avenue and near the Del Paso Heights NAWQA site.
Temporal Representation: | Samples were collected at variable intervals (e.g. every two weeks or monthly) between January 2001 and September 2005.
Environmental Conditions: |
QAPP Information: | Data Qulaity: Good. Minimum requirements for the Surface Water Database are: Name of the sampling agency or organization Date that each sample was collected Date of each sample analysis County where samples were taken Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.) Name or description of water body sampled Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation Description of analytical QA/QC plan, or statement that no formal plan exists Additional optional requirements are included on DPRs webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm.
QAPP Information Reference(s):

DECISION ID | 13251
Pollutant: | Total Petroleum Hydrocarbons
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Four of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is not sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data available may not satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data available may not satisfy the data quantity requirements of section 6.1.5 of the Policy, since they are only for first-flush events. 3. Four of four samples exceed the objective and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. Uncertainty in the representativeness of these samples indicates that they should not be used as the sole basis for listing. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 13251

LOE ID: | 25731
Pollutant: | Total Petroleum Hydrocarbons
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 4
Number of Exceedances: | 4
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Four grab samples were collected from Arcade Creek at Watt Avenue between December 2003 and October 2006 and analyzed for total petroleum hydrocarbons (TPH) as diesel. All four (4 of 4) of the samples exceeded the evaulation guideline (56.0 ug/L). The data used for this assessment were submitted as required by the Waste Discharge Requirements for County of Sacramento and Cities of Citrus Heights, Elk Grove, Folsom, Galt, and Sacramento Storm Water Discharges from Municipal Separate Storm Sewer Systems, Sacramento County (NPDES # CAS082597). Sacramento Stormwater Urban Tributaries. Data obtained from B. Laurenson (Larry Walker Associates) on 18 June 2008.
Data Reference: | Sacramento stormwater urban tributary NPDES permit monitoring data, 2003 to 2007
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | Per the U.S. EPA's "Oral Reference Doses and Oral Slope Factors for JP-4, JP-5, Diesel fuel, and Gasoline" (Dollarhide 1992): The Suggested No Adverse Response Level for total petroleum hydrocarbons as diesel is 56.0 ug/L.
Guideline Reference: | Oral Reference Doses and Oral Slope Factors for JP-4 CAS No. not identified), JP-5 (CAS No. not identified; similar to Kerosene, CAS No. 8008-20-6), Diesel fuel (CAS No. 68334-30-5), and Gasoline (CAS No. 8006-61-9) (AVGAS) [McChord AFB (Wash Rack/Treatment) /Tacoma, WA]
Spatial Representation: | Samples were collected from Arcade Creek at Watt Avenue, in Sacramento County.
Temporal Representation: | Grab samples were collected on the following dates: 14 December 2003, 19 October 2004, 1 December 2005, and 5 October 2006.
Environmental Conditions: |
QAPP Information: | Sampling and analyses were conducted in accordance the Monitoring and Reporting Program Requirements stipulated in Order No. R5-2002-0206 (NPDES No. CAS082597) (CVRWQCB 2002).
QAPP Information Reference(s):

DECISION ID | 11312
Pollutant: | Malathion
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Agriculture | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Five samples exceeded the narrative toxicity water quality 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 section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Five of 76 available calculated 4-day average malathion concentrations exceeded the CDFG criterion continuous concentration (CCC) for the protection of freshwater aquatic life. These excceedances ocurred more than once every three years. In accordance with Section 3.11 of the Listing Policy, this water body should be placed on the 303(d) list.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11312

LOE ID: | 21605
Pollutant: | Malathion
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 76
Number of Exceedances: | 5
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Eighty water samples were collected from Arcade Creek from January 2000 through September 2005, representing seventy-six calculated 4-day average malathion concentrations and eighty 1-hour average malathion concentrations. Five of the seventy-six calculated 4-day average malathion concentrations exceeded the recommended 4-day CCC for malathion of 0.1 ug/L. Zero of the eighty 1-hour average malathion concentrations exceeded the 1-hour average CMC for malathion of 0.43 ug/L.
Data Reference: | Surface Water database (SWDB) for Central Valley waterbodies, 2000-2005
| Correspondence between the Department of Pesticide Regulation and Central Valley Regional Water Quality Control Board regarding water quality data for waterbodies in the Central Valley
Water Quality Objective/Criterion: | All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
| Quality Criteria for Water. USEPA Office of Water and Hazardous Materials. Washington, D.C
Evaluation Guideline: | The US EPA recommended 4-day average, criterion continuous concentration (CCC) is 0.1 ug/L (US EPA, 1976). The California Department of Fish and Game Hazard Assessment Criterion 1-hour average, concentration (CMC) is 0.43 ug/L (CDFG, 1998).
Guideline Reference: | Hazard Assessment of the Insecticide Malathion to Aquatic Life in the Sacramento-San Joaquin River System. California Department of Fish and Game. Office of Spill Prevention and Response Administrative Report 98-2
Spatial Representation: | Samples were collected from Arcade Creek at Norwood and near Del Paso Heights.
Temporal Representation: | Samples were collected at variable intervals (e.g. biweekly and monthly) from January 2000 through September 2005.
Environmental Conditions: | Arcade Creek is an urban creek in the greater Sacramento area.
QAPP Information: | Data quality: Good. Minimum requirements for the CDPR Surface Water Database are: Name of the sampling agency or organization, Date that each sample was collected, Date of each sample analysis, County where samples were taken, Detailed sampling location information (including latitude and longitude or township/range/section if available), detailed map or description of each sampling site (i.e., address, cross roads, etc.), Name or description of water body sampled, Name of the active ingredient analyzed for; concentration detected (with unit of measurement), and limit of quantitation, Description of analytical QA/QC plan, or statement that no formal plan exists. Additional optional requirements are included on DPR's webpage at http://www.cdpr.ca.gov/docs/emon/surfwtr/caps/req.htm
QAPP Information Reference(s): | Standard Operating Procedure for Conducting Surface Water Monitoring for Pesticides

DECISION ID | 11315
Pollutant: | Pyrethroids
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Sources: | Urban Runoff/Storm Sewers
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Weight of Evidence: | This pollutant is being considered for placement on the section 303(d) list under Sections 3.6 and 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Four of five sediment samples collected from Arcade Creek in the City of Sacramento were in violation of the narrative toxicity objective due to occurrences of statistically significant sediment toxicity, and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. Sediment-bound pyrethroid pesticide concentrations were used to calculate toxic units (TUs) of multiple pyrethroid pesticides observed in sediments. Pyrethroid TU analyses correlated with distribution and magnitude of toxicity. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
RWQCB Board Decision / Staff 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.
SWRCB Board Decision / Staff Recommendation: |
USEPA Decision: |

Lines of Evidence (LOEs) for Decision ID 11315

LOE ID: | 21582
Pollutant: | Pyrethroids
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 4
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | Four of five sediment toxicity testing samples violated the narrative toxicity objective. The four toxic sediment samples were collected from Arcade Creek at Auburn Boulevard and had (Mean mortality +/- standard deviation) values, by date: on10/15/04 :(98+/-4.6), on 10/24/04 (53+/-29.6), on 3/10/05 (38+/-12.8), on 8/12/05 (29+/-16.4). Toxicity observations were associated with pyrethroid pesticides. LC50s for sediment-bound pyrethroids were used in this study as toxicity threshold benchmarks in a Toxic Unit (TU) analysis normalized to organic carbon content. The TU analysis of Arcade Creek sediment samples demonstrated that the four toxic samples had pyrethroid pesticide concentrations that would be expected to be acutely toxic. The only nontoxic sample was collected from Arcade Creek at Sylvan Road on 8/31/2004 and had 0.68 TUs of pyrethroids. The remaining four toxic samples were collected from Arcade Creek at Auburn Boulevard on October 15, 2004, October 24, 2004, March 10, 2005, and August 12, 2005, and had an average of 1.20 to 3.87 TUs of pyrethroid pesticides. Bifenthrin appears to play a dominant role in the toxicity observations, but was not the only pyrethroid found in toxic sediment samples. Other pyrethroids observed in the toxic samples from Arcade Creek included cyfluthrin, cypermethrin, deltamethrin, lambda-cyhalothrin, and permethrin. LC50 concentrations for a 10-day exposure of Hyalella azteca to pyrethroid contaminated sediments were determined by Amweg et al., 2005. (Amweg, E.L., D.P. Weston, and N.M Ureda. 2005. Use and toxicity of pyrethroid pesticides in the Central Valley, California, U.S.A. Environ. Toxicol. Chem. 24:966-972 (with correction in Environ. Toxicol. Chem. 24:1300-1301)).
Data Reference: | Pyrethroid insecticides and sediment toxicity in urban creeks from California and Tennessee. Environmental Science and Technology, 40(5): 1700-1706
Water Quality Objective/Criterion: | No individual pesticide or combination of pesticides shall be present in concentrations that adversely affect beneficial uses. (CVRWQCB, 2007). All waters shall be maintained free of toxic substances in concentrations that produce detrimental physiological responses in human, plant, animal, or aquatic life (CVRWQCB, 2007)
Objective/Criterion Reference: | Central Valley Regional Water Quality Control Board. Water Quality Control Plan (Basin Plan) for the California Regional Water Quality Control Board - Central Valley Region
Evaluation Guideline: | Statistically significant difference from control sediment using Dunnetts test in 10-day Hyalella azteca sediment toxicity tests. Arcsin squareroot transformation was used when necessary to meet the assumptions of normality and homogeneity of variance. Steels test was used for comparison to control if these assumptions were not met after transformation
Guideline Reference:
Spatial Representation: | Five samples were collected from two Arcade Creek locations. On 31 August 2004, the sample collected at Sylvan Road was was nontoxic. Sediment toxicity was observed in all four samples collected at Auburn Boulevard on 15 October 2004, 24 October 2004, 10 March 2005, and 12 August 2005. Arcade Creek sampling locations reflect mixed commercial and residential land uses
Temporal Representation: | Samples were collected between August 2004 and August 2005.
Environmental Conditions: |
QAPP Information: | Data quality: Excellent. Monitoring was conducted in accordance with the Quality Assurance Project Plan for Monitoring prepared for the Sacramento River Watershed Program (SRWP 1999a, 1999b, 2000b, 2001b, 2002b, 2003b, 2006).
QAPP Information Reference(s):