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Aquatic Life Criteria

An Online Basic Course

Fishes in a pondStates or tribes need to address aquatic life criteria in their water quality standards along with human health, nutrient, and biological criteria. This Aquatic Life Criteria online module, designed by EPA’s Office of Science and Technology for state and tribal employees and the general public, explains what aquatic life criteria are and the calculations involved in establishing them. The majority of EPA’s aquatic life criteria used today was derived using EPA’s Guidelines for Deriving Numerical National Water Quality Criteria for the Protection of Aquatic Organisms and Their Use.