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Animal Feeding Operations - Regulations, Guidance, and Studies
AFOs Topics * AFOs Overview * NPDES CAFO Permitting * Regulations, Guidance, and Studies * Compendium of State Permits and Programs * Outreach and Education * Uses of Manure * Technology and Innovation * Understanding Nutrient Management Plans
On this page: * Study * Regulations * Guidance
Study
2023
As announced in the Effluent Guidelines Program Plan 15 (January 2023), EPA intends to undertake a detailed study of the Concentrated Animal Feeding Operations (CAFOs) Category, which will focus on collecting further information to enable the Agency to make an informed, reasoned decision whether to undertake rulemaking to revise the ELG for CAFOs. * Current Effluent Guidelines Program Plan
Regulations
2014
Regulatory Flexibility Act Section 610 Review of the National Pollutant Discharge Elimination System (NPDES) Permit Regulation and Effluent Limitations Guidelines and Standards for Concentrated Animal Feeding Operations (CAFOs) - Review of the 2003 NPDES permit regulation and effluent limitations guidelines (ELG) standards for CAFOs pursuant to section 610 of the Regulatory Flexibility Act (RFA). * Regulatory Flexibility Act Section 610 Review of the National Pollutant Discharge Elimination System (NPDES) Permit Regulation and Effluent Limitations Guidelines and Standards for Concentrated Animal Feeding Operations (CAFOs) (June 3, 2014)Exit EPA’s website * Federal Register Notice: Request for Comments (77 FR 65840) (October 31, 2012)Exit EPA’s website * Federal Register Notice of Extension of Comment Period (78 FR 277) (January 3, 2013)(PDF)Exit EPA’s website(2 pp, 139 K, About PDF)
2012
EPA Administered Permit Programs: The National Pollutant Discharge Elimination System - This document consolidates the current federal CAFO regulatory requirements included in the 2012 CAFO rule revision to remove the Fifth Circuit Court’s vacated elements, and the 2008 and 2003 final CAFO rules into a single document. * Compiled CAFO Final Rule (July 30, 2012)
National Pollutant Discharge Elimination System (NPDES) Concentrated Animal Feeding Operation (CAFO) Reporting Rule - EPA co-proposed two options for obtaining basic information from CAFOs to support EPA in meeting its water quality protection responsibilities under the Clean Water Act (CWA). EPA withdrew the proposed rule in 2012. * Proposed Rule, October 21, 2011 (PDF)Exit EPA’s website(28 pp, 1,005 KB, About PDF) * Extension of Public Comment Period, December 19, 2011 (PDF)Exit EPA’s website(3 pp, 158 K, About PDF) * Withdrawal, July 20, 2012 (PDF)Exit EPA’s website(4 pp, 220 K, About PDF)
National Pollutant Discharge Elimination System Permit Regulation for Concentrated Animal Feeding Operations: Removal of Vacated Elements in Response to 2011 Court Decision - EPA revised provisions of the 2008 CAFO rule that the Fifth Circuit Court of Appeals had vacated; in particular clarifying that CAFOs are required to have permits when they discharge as opposed to when they propose to discharge. * Final Rule, July 30, 2012 (PDF)Exit EPA’s website(4 pp, 277 K, About PDF)
2008
Revised National Pollutant Discharge Elimination System Permit Regulation and Effluent Limitations Guidelines for Concentrated Animal Feeding Operations in Response to the Waterkeeper Decision- This final rule furthers the statutory goal of restoring and maintaining the nation’s water quality by ensuring that CAFOs properly manage manure generated by their operations. * Proposed Revised Rule (June 22, 2006) * Proposed Supplemental Revised Rule (March 7, 2008) (PDF)Exit EPA’s website(20 pp, 225 KB, About PDF) * Final Revised Rule (November 20, 2008) (PDF)Exit EPA’s website(69 pp, 1,208 KB, About PDF)
2003
National Pollutant Discharge Elimination System Permit Regulation and Effluent Limitation Guidelines and Standards for Concentrated Animal Feeding Operations (CAFOs) - Revises and clarifies the EPA's regulatory requirements for CAFOs under the CWA. This final rule ensures that CAFOs take appropriate actions to manage manure effectively in order to protect the nation's water quality. The rule revises two sections of the Code of Federal Regulations (CFR), the NPDES permitting requirements for CAFOs (Sec. 122), and ELGs for CAFOs (Sec. 412). * Final Rule (February 12, 2003) (PDF)Exit EPA’s website(99 pp, 1,217 KB, About PDF) * Table of Contents: Cross-Reference Guide to Federal Register page numbers for 2003 Final Rule (February 12, 2003)
Guidance
NPDES Permit Writers' Manual for Concentrated Animal Feeding Operations (CAFOs) - Provides information to states, producers, and the general public including: * general information on Clean Water Act (CWA) and NPDES requirements for CAFOs, * information to explain CAFO permitting requirements under the CWA, and * technical information to help states and producers understand options for nutrient management planning.
Regulatory Definitions of Large CAFOs, Medium CAFOs, and Small CAFOs - This factsheet defines a large, medium, and small concentrated animal feeding operation (CAFO).
National Pollutant Discharge Elimination System (NPDES)
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