Section 434.52 - Effluent limitations quidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT)(a)Reclamation areas. The limitations in this subsection apply to discharges from reclamation areas until the performance bond issued to the facility by the appropriate SMCRA authority has been released. Except as provided in 40 CFR 125.30-125.32 , 40 CFR 401.17 and §§ 434.61 and 434.63(d)(2) of this part, the following limitations establish the concentration or quality of pollutants which may be discharged by a point source subject to the provisions of this subsection after application of the best practicable control technology currently available:
BPT Effluent Limitations
| Pollutant or pollutant property | Limitations |
| Settleable Solids | 0.5 ml/l maximum not to be exceeded. |
| pH | (1) |
1 Within the range 6.0 to 9.0 at all times.
(b)Underground mine drainage. The limitations in this subsection apply to discharges from the underground workings of underground mines until SMCRA bond release.(1) Except as provided in 40 CFR 125.30-125.32 , 40 CFR 401.17 and §§ 434.61 , 434.62 and 434.63 of this part, the following limitations establish the concentration of quality of pollutants in acid or ferruginous mine drainage subject to the provisions of this subsection after application of the best practicable control technology currently available: BPT Effluent Limitations
| Pollutant or pollutant property | Maximum for any 1 day | Average of daily values for 30 consecutive days |
| Concentration in mg/l |
| Iron, total | 7.0 | 3.5 |
| Manganese, total | 4.0 | 2.0 |
| TSS | 70.0 | 35.0 |
| pH | (1) | (1) |
1 Within the range 6.0 to 9.0 at all times.
(2) Except as provided in 40 CFR 125.30-125.32 , 40 CFR 401.17 , and §§ 434.61 and 434.63 of this part, the following limitations establish the concentration or quality of pollutants in alkaline mine drainage subject to the provisions of this subsection after application of the best practicable control technology currently available: BPT Effluent Limitations
| Pollutant or pollutant property | Maximum for any 1 day | Average of daily values for 30 consecutive days |
| Concentration in mg/l |
| Iron, total | 7.0 | 3.5 |
| TSS | 70.0 | 35.0 |
| pH | (1) | (1) |
1 Within the range 6.0 to 9.0 at all times.