The 2018 General Assembly approved HB 1475 and SB 344, which were signed by the Governor on March 29, 2018, with an effective date of July 1, 2018 (Attachment 1). This legislation dealt with the State Water Control Board’s (Board) adoption of the U.S. Environmental Protection Agency’s (EPA) recommended changes to freshwater ammonia criteria, requiring that the Board include in such adoption a phased implementation program (PIP) consistent with the federal Clean Water Act. EPA updated its 1999 Clean Water Act § 304(a) national ambient water quality criteria recommendations for ammonia in 2013. These criteria are approximately twice as stringent as the current criteria in Virginia’s Water Quality Standards Regulation (9VAC25-260-155) since they reflect added toxicity data for very sensitive freshwater mussels and snails. Including the PIP in the adoption of the new ammonia criteria was intended to address potential impacts on permitted dischargers across the state that will need extended compliance schedules and may be affected by fiscal stress.

HB 1475 and SB 344 also directed the Department of Environmental Quality (DEQ) to provide certain additional information to the General Assembly, no later than November 1, 2018. Specifically, HB 1475 and SB 344 asked DEQ to:

• Identify any other states that have adopted EPA’s 2013 Aquatic Life Ambient Water Quality Criteria for Ammonia as of July 1, 2018.

• Identify the specific procedures and practices for the implementation of the freshwater ammonia criteria that will both minimize the impact of the criteria on Virginia sewerage systems or other treatment works and be permissible under the federal Clean Water Act (33 U.S.C. § 1251 et seq.), including an opportunity to request consideration of alternative effluent limitations based on a demonstration by the permittee, acceptable to the Board, of the lack of appreciable harm from the discharge of ammonia to aquatic life that is present in the vicinity of the discharge or which should be present but for the discharge.

As of July 1, 2018, five states have adopted EPA’s 2013 nationally-recommended freshwater ammonia criteria: California, Florida, Kansas, Oregon, and Vermont. Additional states are in various stages of adopting the 2013 freshwater ammonia criteria.

DEQ has identified three options specifically identified in the Water Quality Standards regulation (9VAC25-260-140. Criteria for Surface Water) that provide partial relief for permitted dischargers from the 2013 nationally-recommended ammonia criteria in Virginia. These options are the most relevant among the collection of flexibilities allowed under Clean Water Act that States can utilize when confronted with implementation of challenging water quality criteria. The first option is the Statewide Phased Implementation Program required by HB 1475 and SB 344. The second option is a water quality standard (WQS) variance. Lastly, the 2013 nationally-recommended ammonia criteria can be recalculated to account for the absence of freshwater mussels at a particular site.

In addition to the three options specifically identified in the Virginia Water Quality Standards regulation (9VAC 25-260) identified above, there are numerous considerations taken into account by the DEQ permit writer in establishing an appropriate effluent limitation. Some of these considerations include the determination of appropriate pH and temperature values, evaluation of stream and discharge flows, the use of actual as opposed to potential effluent ammonia concentrations, seasonal tiering of effluent limits, effluent variability, appropriate application of the Board’s Antidegradation Policy in accordance with 9VAC 260-30, consideration of other related parameters that may be more limiting, etc. DEQ has formed an implementation workgroup that is currently evaluating these and other factors related specifically to the proposed nationally-recommended freshwater ammonia criteria. It is expected that revisions to current guidance will provide some relief to permitted dischargers in addition to that offered by the three alternatives identified above and discussed more fully in this report.