§ 421.95 Pretreatment standards for existing sources.
Current through Aug 22, 2025 · Read all of Part 421
Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for existing sources. The mass of wastewater pollutants in metallurgical acid plant blowdown introduced into a POTW shall not exceed the following values:
Subpart I—Metallurgical Acid Plant—PSES
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pound per/million pounds) of 100 pct sulfuric acid capacity | ||
| Cadmium | 0.511 | 0.204 |
| Zinc | 2.605 | 1.073 |
[50 FR 38343, Sept. 20, 1985]