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Title 40

Displaying title 40, up to date as of 8/14/2026. Title 40 was last amended 8/14/2026.
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§ 425.35 Pretreatment standards for existing sources (PSES).

(a) Except as provided in § 425.04 and 40 CFR 403.7 and § 403.13, any existing sources subject to this subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403, and achieve the following pretreatment standards:

Pollutant or pollutant property PSES limitations
Maximum for any 1 day Maximum for monthly average
Milligrams per liter (mg/l)
Sulfide 24
Total Chromium 12 8
pH (1) (1)
1 Not less than 7.0.

(b) Any existing source subject to this subpart which processes less than 350 hides/day shall comply with § 425.35(a), except that the Total Chromium limitations contained in § 425.35(a) do not apply.

[47 FR 52870, Nov. 23, 1982; 48 FR 36116, June 30, 1983, as amended at 53 FR 9182, Mar. 21, 1988]