General

General

Washington state updates Aquatic Life Toxics Criteria for the first time in 30 years, becomes first state to set criteria for 6PPD

The Washington State Department of Ecology recently published significant updates to the aquatic life toxics criteria for the first time since the early 1990s. The new criteria establish limits for 42 chemicals, including a first-in-the-nation numeric freshwater limit for 6PPD quinone, a chemical that is especially toxic for salmon and trout. Ecology also updated the criteria to include PFAS, making it one of the first states to implement EPA’s draft criteria for PFAS. And, Ecology updated criteria for numerous naturally occurring background metals, which may present challenges for NPDES permit holders in certain receiving waters. Ecology will use the updated criteria to establish water quality standards that generate the need for total maximum daily loads (TMDLs) and determine discharge limits in NPDES permits.