Permitting Strategies & Reasonable Potential Analysis

Water quality based limitations (WQBLs) are imposed in wastewater permits when it is determined that technology based limitations are not sufficient to protect water quality (40 CFR 125.3). These limitations are based on state and federal water quality standards, as well as the assimilative capacity of the receiving stream.

EPD has developed a number of permitting strategies and reasonable potential analysis procedures to aid in the determination of effluent limitations in NPDES wastewater permits. More information on the development of limitations may be found on the Water Quality Modeling page.

NPDES Reasonable Potential Procedures

Ammonia

• Ammonia NPDES Strategy
• Flexibilities for States Applying EPA’s Ammonia Criteria Recommendations (EPA-820-F-13-001)
• Ammonia Reasonable Potential Analysis Procedure for NPDES Permits, May 2017
• Example Reasonable Potential Analysis Worksheet
• Sample Permit Conditions Ammonia Compliance Schedule and Recalculation Procedure – Industrial
• Sample Permit Conditions Ammonia Compliance Schedule and Recalculation Procedure – Municipal

Phosphorus

• Phosphorous Strategy

Total Residual Chlorine

• Total Residual Chlorine Strategy

Whole Effluent Toxicity

• WET Strategy
• WET Memo

DRAFT Bacteria Strategy

Draft Bacteria Equivalency Strategy for Using the Optimal Indicator Organisms for WQS and NPDES Permitting (Bacteria Strategy)

During the 2013 Triennial Review, Georgia adopted E. coli and enterococci as the pathogen indicators for waters designated as recreation where primary contact recreational activities such as swimming, water skiing, and white-water boating occur. As part of the 2019 Triennial Review, Georgia proposed E. coli and enterococci criteria for waters designated as fishing, coastal fishing, and drinking water to protect secondary contact recreators who may inadvertently ingest water. The Bacteria Equivalency Strategy for Using the Optimal Indicator Organisms for WQS and NPDES Permitting (Bacteria Strategy) provides a framework for the implementation of the proposed changes to the bacteria criteria for water quality monitoring, 303(d)/305(b) listing purposes, Total Maximum Daily Loads, and wastewater and stormwater permitting.

Bacteria Strategy

A stakeholder meeting to discuss the Bacteria Strategy was held on Tuesday, December 14. A copy of the presentation is available for download.