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U.S. Code of Federal Regulations
Regulations most recently checked for updates: Oct 07, 2025
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Title 40
Chapter I
Part 131
Subpart D - Subpart D—Federally Promulgated Water Quality Standards
View all text of Subpart D [§ 131.31 - 131.48]
131.48 - 131.48 xxx
Link to an amendment published at 90 FR 46508, Sept. 29, 2025.
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