40 CFR § 434.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).

---
identifier: "/us/cfr/t40/s434.42"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 434.42 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT)."
title_number: 40
title_name: "Protection of Environment"
section_number: "434.42"
section_name: "Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT)."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "N"
subchapter_name: "EFFLUENT GUIDELINES AND STANDARDS"
part_number: "434"
part_name: "COAL MINING POINT SOURCE CATEGORY BPT, BAT, BCT LIMITATIONS AND NEW SOURCE PERFORMANCE STANDARDS"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "33 U.S.C. 1311 1314(b), (c), (e), and (g), 1316(b) and (c), 1317(b) and (c), and 1361."
regulatory_source: "50 FR 41305, Oct. 9, 1985, unless otherwise noted."
cfr_part: "434"
---


# 434.42 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).

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 which may be discharged by a point source subject to the provisions of this subpart 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. | 35. |
| pH | () | () |
| Within the range 6.0 to 9.0 at all times. |  |  |