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Section 404 of the Clean Water Act

Memorandum: Assessment of Stream Ecosystem Structure and Function under Clean Water Act Section 404 Associated with Review of Permits for Appalachian Surface Coal Mining

This document clarifies the agencies’ interpretation of current regulatory requirements at 40 CFR 230.11(e) for determining “the nature and degree of effect that the proposed discharge will have…on the structure and function of the aquatic ecosystem and organisms.”

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