421.92—Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.
Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart must achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT):
| Pollutant or pollutant property | BPT effluent limitations | |
|---|---|---|
| Maximum for any 1 day | Maximum for monthly average | |
| mg/kg (pounds per million pounds of 100% sulfuric acid capacity | ||
| Cadmium | 0.180 | 0.090 |
| Copper | 5.000 | 2.000 |
| Lead | 1.800 | 0.790 |
| Zinc | 3.600 | 0.900 |
| Fluoride 1 | 212.800 | 121.000 |
| Molybdenum 1 | 40.180 | 20.790 |
| Total suspended solids | 304.000 | 152.000 |
| pH | 2 | 2 |
| 1 For Molybdenum Acid Plants Only. | ||
| 2 Within the range of 6.0 to 9.0 at all times. | ||
[50 FR 38342, Sept. 20, 1985; 50 FR 52776, Dec. 26, 1985]