1 / 6

REASONABLE POTENTIAL DETERMINATIONS

REASONABLE POTENTIAL DETERMINATIONS. National WET Guidance. Issued in November 2004 as “Draft” Guidance Three goals: National consistency in WET implemention NPDES regulatory compliance Emphasize existing guidance, policy, and regulations EPA Region 6 policy May 2005

ismael
Download Presentation

REASONABLE POTENTIAL DETERMINATIONS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. REASONABLE POTENTIALDETERMINATIONS

  2. National WET Guidance • Issued in November 2004 as “Draft” Guidance • Three goals: • National consistency in WET implemention • NPDES regulatory compliance • Emphasize existing guidance, policy, and regulations • EPA Region 6 policy May 2005 • Sublethal RP determinations • WET Limits to include sublethal endpoints

  3. 40 CFR 122.44(d) • Must determine whether the discharge causes, has reasonable potential to cause, or contributes to non-attainment of the narrative criterion in the water quality standards for WET. • If the determination is positive, WET limits must be included in the permit.

  4. 40 CFR 122.44(d) • Requires an RP determination, but does not require the use of a specific procedure • EPA Region 6 is requiring a modified 1991 Technical Support Document (TSD) approach, meaning two or more failures equals RP • TCEQ has developed an alternate risk based approach

  5. TCEQ Approach • Use RP decision tree • More than 3 failures in past five years, or 3 failures with 2 in the past three years, equals RP • 2 or more failures in past five years, but less than above, requires a BPJ approach • BPJ approach uses “weight of evidence” approach, accounting for duration and magnitude of test failures

  6. Unresolved Issues • The Implementation Procedures document is currently with EPA for review and comment. • EPA has not approved the proposed IP WET requirements, RP determination method, or consideration of BPJ factors. • Additionally, EPA is currently objecting to default 3 year compliance periods . EPA is requiring shorter compliance periods, enforceable interim milestones, and justification of the compliance period.

More Related