Except as provided in § 425.04 and 40 CFR 403.7 and § 403.13, any existing source 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 | |
|---|---|---|
| Maximum for any 1 day | Maximum for monthly average | |
| Milligrams per liter (mg/l) | ||
| Sulfide | 24 | |
| Total chromium | 12 | 8 | 
| pH | (1) | (1) | 
[47 FR 52870, Nov. 23, 1982, as amended at 61 FR 35685, July 8, 1996]