Draft California 2014 Integrated Report (303(d) List/305(b) Report)

Supporting Information

Regional Board 4 - Los Angeles Region

Water Body Name: Rustic Canyon Creek
Water Body ID: CAR4051300020050622200110
Water Body Type: River & Stream
Region 4     
Rustic Canyon Creek
Pollutant: Sulfates
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)(2012)
Revision Status Original
Impairment from Pollutant or Pollution: Pollutant
Regional Board Staff Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status.

One line of evidence is available in the administrative record to assess this pollutant. An insufficient total number of samples were taken and an insufficient number of samples exceed the MCL guideline for Sulfate.

Based on the readily available data and information, the weight of evidence indicates that there is insufficient 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 four samples exceeded the MCL guideline. More data is needed to determine if the water quality standard is exceeded.
4.Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: This is a decision previously approved by the State Water Resources Control Board and the USEPA. No new data were assessed by the Regional Board for the current cycle. The decision has not changed.
Line of Evidence (LOE) for Decision ID 33437, Sulfates
Region 4     
Rustic Canyon Creek
LOE ID: 2422
Pollutant: Sulfates
LOE Subgroup: Pollutant-Water
Matrix: Water
Fraction: Not Recorded
Beneficial Use: Municipal & Domestic Supply
Number of Samples: 4
Number of Exceedances: 4
Data Used to Assess Water Quality: Four samples with four exceeding. (SWAMP, 2004).
Data Reference: Placeholder reference 2006 303(d)
Water Quality Objective/Criterion: CCR- Title 22 Table 64449-B Secondary Maximum Contaminant Levels of 250 mg/l for Sulfate.
Objective/Criterion Reference: Placeholder reference 2006 303(d)
Evaluation Guideline:
Guideline Reference:
Spatial Representation: Two stations at Rustic Canyon Creek Upper: 34.05101 -118.5111and at Rustic Canyon Creek Lower: 34.03361 -118.51787.
Temporal Representation: Samples were collected March 2003 through March 2004.
Environmental Conditions: Los Angeles County Coastal Streams: 405.13.
QAPP Information: SWAMP Quality Assurance Plan.
QAPP Information Reference(s):