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Standard Analytical Methods Updates

Standard Analytical Methods Updates

DEC Water Quality Standards (WQS) Staff propose new regulatory language and updated citations to ensure that analytical methods at 18 AAC 70.020, 18 AAC 70.030 and 18 AAC 83.010 are consistent with Clean Water Act (CWA) approved methods in 40 CFR Part 136.

What Will Be Updated?

  1. Revision of fecal coliform criteria for harvesting for consumption use to
    • specify a 30-day sampling period, and
    • allow testing by either membrane filtration or most probable number (MPN) methods.
  2. Updates to notes in the Water Quality Standards table in 18 AAC 70.020(b) for
    • Fecal coliform
    • Radiation
  3. Updates to CWA approved analytical methods adopted by reference in 18 AAC 70.020(c).
  4. Updates to whole effluent toxicity method in 18 AAC 70.030.
  5. Update to Code of Federal Regulation reference (40 CFR Part 136) date at 18 AAC 83.010(f).


EPA 2012 Final Rule: CWA Analytical Methods

Under CWA section 304(h), DEC's clean water programs are required to use EPA-approved analytical methods listed in 40 CFR Part 136 and adopted in state regulations at 18 AAC 70.020(c). EPA issued a final rule with new and revised analytical methods in   2012. The DEC Quality Assurance Officer and WQS section do not consider any of the proposed changes to be controversial or to cause implementation concerns. EPA will review the changes, but approval is not required when adopting CWA-approved analytical methods.

The final EPA rule approves CWA methods published by (1) EPA, (2) voluntary consensus organizations (e.g., American Society for Testing and Materials International and the Standard Methods Committee), and (3) certain commercial entities. The new rule provides additional guidance on quality assurance/quality control requirements and changes to sample collection, preservation, and holding times.

National Pollutant Discharge Elimination System (NPDES): Use of Sufficiently Sensitive Test Methods for Permit Applications and Reporting

EPA has modified its regulation for NPDES permit applications, compliance monitoring, and analytical methods in 40 CFR Part 122 and 136. The final rule can be found at   National Pollutant Discharge Elimination System (NPDES): Use of Sufficiently Sensitive Test Methods for Permit Applications and Reporting.

The final rule requires that, where EPA-approved methods exist, NPDES applicants must use sufficiently sensitive EPA-approved analytical methods when quantifying the presence of pollutants in a discharge and that the Director [1]  must prescribe only sufficiently sensitive EPA-approved methods be used for analyses of pollutants or pollutant parameters under the permit.

The new federal rule is consistent with longstanding permitting procedures and current Alaska Pollutant Discharge Elimination System (APDES) permits that include the following condition:

"For all effluent monitoring, the permittee must use a test method that can achieve a method detection limit (MDL) less than the effluent limitation. For a parameter without an effluent limitation, the permittee must use the most sensitive MDL from an EPA-approved analytical test necessary for compliance monitoring."
[1]  "Director" refers to the permitting authority. Per 40 CFR 122.2, "Director" means the Regional Administrator or the state Director, as the context requires, or an authorized representative. When there is no "approved State Program" and there is an EPA-administered program, "Director" means the Regional Administrator. When there is an approved State program, "Director" normally means the State Director. In some circumstances, however, EPA retains the authority to take certain actions even when there is an approved State program.