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Water Quality Standards: Establishment of a Numeric Criterion for Selenium for Fresh Waters in California


On November 29, 2018, EPA Acting Administrator Wheeler signed a proposed rule to revise the current federal Clean Water Act selenium water quality criterion applicable to certain fresh waters of California. This rule, Establishment of a Numeric Criterion for Selenium for the State of California, is being proposed to ensure that the criterion is set at a level that protects aquatic life and aquatic-dependent wildlife. The EPA promulgated California’s existing selenium criterion for certain fresh waters in 2000 as part of the California Toxics Rule, using the EPA’s recommended aquatic life chronic freshwater criterion value at the time. However, the latest science indicates that the existing criterion may not be protective of aquatic life and aquatic-dependent wildlife. 

Public Hearings

Comments on the Proposal

The comment period for this proposal opened on December 13, 2018 and closed on March 28, 2019.

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