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National Pollutant Discharge Elimination System (NPDES)

NPDES AFOs Policy Documents


Regulatory Definitions of Large CAFOs, Medium CAFOs, and Small CAFOs (PDF) (May 18, 2011) (1 pg, 22K) -- This factsheet defines large, medium, and small concentrated animal feeding operations (CAFO).


Policy on Using the Clean Water State Revolving Fund to Finance Section 320 Comprehensive Conservation and Management Plan Projects (PDF) (March 1, 2001) (4 pp, 219KB) -- Phase I or Phase II stormwater permits issued to CAFOs and stormwater programs cannot be defined and receive funding as nonpoint source pollution. This memorandum clarifies that they are eligible for funding if the project is included in the state’s approved National Estuary Program's Comprehensive Conservation and Management Plan (CCMP). 


Unified National Strategy for Animal Feeding Operations -- Document sets forth a framework of actions, for USDA and EPA under existing legal and regulatory authority, to reduce impacts to water quality and public health from improperly managed animal wastes.


Policy Statement on Scope of Discharge Authorization and Shield Associated with NPDES Permits (PDF) (July 1, 1994) (332KB) -- EPA's position on the scope of the authorization to discharge under an NPDES permit and the shield thus associated with the permit authorization.