Section 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