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Title 40

Displaying title 40, up to date as of 7/09/2026. Title 40 was last amended 7/09/2026.
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  1. Title 40 —Protection of Environment
  2. Chapter I —Environmental Protection Agency
  3. Subchapter D —Water Programs
  4. Part 125   View Full Text
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter DWater Programs100 – 149
Part 125Criteria and Standards for the National Pollutant Discharge Elimination System125.1 – 125.139
Subpart ACriteria and Standards for Imposing Technology-Based Treatment Requirements Under Sections 301(b) and 402 of the Act125.1 – 125.3
§ 125.1Purpose and scope.
§ 125.2Definitions.
§ 125.3Technology-based treatment requirements in permits.
Subpart BCriteria for Issuance of Permits to Aquaculture Projects125.10 – 125.11
§ 125.10Purpose and scope.
§ 125.11Criteria.
Subpart C [Reserved]
Subpart DCriteria and Standards for Determining Fundamentally Different Factors Under Sections 301(b)(1)(A), 301(b)(2) (A) and (E) of the Act125.30 – 125.32
§ 125.30Purpose and scope.
§ 125.31Criteria.
§ 125.32Method of application.
Subpart E—Criteria for Granting Economic Variances From Best Available Technology Economically Achievable Under Section 301(c) of the Act [Reserved]
Subpart F—Criteria for Granting Water Quality Related Variances Under Section 301(g) of the Act [Reserved]
Subpart GCriteria for Modifying the Secondary Treatment Requirements Under Section 301(h) of the Clean Water Act125.56 – 125.68
Subpart HCriteria for Determining Alternative Effluent Limitations Under Section 316(a) of the Act125.70 – 125.73
Subpart IRequirements Applicable to Cooling Water Intake Structures for New Facilities Under Section 316(b) of the Act125.80 – 125.89
Subpart JRequirements Applicable to Cooling Water Intake Structures for Existing Facilities Under Section 316(b) of the Clean Water Act125.90 – 125.99
Subpart K [Reserved]
Subpart L—Criteria and Standards for Imposing Conditions for the Disposal of Sewage Sludge Under Section 405 of the Act [Reserved]
Subpart MOcean Discharge Criteria125.120 – 125.124
Subpart NRequirements Applicable to Cooling Water Intake Structures for New Offshore Oil and Gas Extraction Facilities Under Section 316(b) of the Act125.130 – 125.139
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