EPA Drops Bifurcated Approach For Strict Ammonia Water Quality Criteria

摘要

EPA has unveiled strict new water quality criteria for ammonia, dropping a bifurcated approach that the Fish & Wildlife Service (FWS) had urged the agency to eliminate from an earlier proposal while also providing flexibilities sought by the wastewater sector, including greater use of site-specific factors. According to a Federal Register notice published Aug. 22, EPA is issuing recommended water quality criteria - risk-based concentrations that regulators use to craft permits, water quality standards and other regulatory limits - to protect freshwater aquatic species from high levels of ammonia. The notice is available on InsideEPA.com. Seepage 2 for details. (Doc ID: 2444534) The new criteria for chronic exposures recommends a range of 0.99 milligrams of total ammonia nitrogen (TAN) per liter (TAN/L) at 30°Celsius to 4.4 mg TAN/L at 0°Celcsius at neutral pH. EPA sets the chronic standard at 1.9 milligrams of ammonia nitrogen per liter (mg/L) at a neutral pH and 20° Celsius temperature.