40 CFR § 421.213 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.
---
identifier: "/us/cfr/t40/s421.213"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 421.213 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable."
title_number: 40
title_name: "Protection of Environment"
section_number: "421.213"
section_name: "Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "N"
subchapter_name: "EFFLUENT GUIDELINES AND STANDARDS"
part_number: "421"
part_name: "NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "Secs. 301, 304 (b), (c), (e), and (g), 306 (b) and (c), 307 (b) and (c), 308 and 501 of the Clean Water Act (the Federal Water Pollution Control Act Amendments of 1972, as amended by the Clean Water Act of 1977) and the Water Quality Act of 1987 (the “Act”); 33 U.S.C. 1311, 1314 (b), (c), (e), and (g), 1316 (b) and (c), 1317 (b) and (c), 1318 and 1361; 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217; 101 Stat. 7, Pub. L. 100-4."
regulatory_source: "49 FR 8790, Mar. 8, 1984, unless otherwise noted."
cfr_part: "421"
---
# 421.213 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.
Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable:
(a) Molybdenum sulfide leachate.
BAT Limitations for the Primary Molybdenum and Rhenium Subcategory
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
| | mg/kg (pounds million pounds) of molybdenum sulfide leached | |
| Arsenic | 0.644 | 0.287 |
| Lead | 0.130 | 0.060 |
| Nickel | 0.255 | 0.171 |
| Selenium | 0.380 | 0.171 |
| Molybdenum | [Reserved] | [Reserved] |
| Ammonia (as N) | 61.720 | 27.130 |
| Fluoride | 16.210 | 9.214 |
(b) Roaster SO<sub>2</sub> scrubber.
BAT Limitations for the Primary Molybdenum and Rhenium Subcategory
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
| | mg/kg (pounds per/million pounds) of molybdenum sulfide roasted | |
| Arsenic | 2.334 | 1.041 |
| Lead | 0.470 | 0.218 |
| Nickel | 0.924 | 0.621 |
| Selenium | 1.377 | 0.621 |
| Molybdenum | [Reserved] | [Reserved] |
| Ammonia (as N) | 223.800 | 98.390 |
| Fluoride | 58.770 | 33.410 |
(c) Molybdic oxide leachate.
BAT Limitations for the Primary Molybdenum and Rhenium Subcategory
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
| | mg/kg (pounds per/million pounds) of molybdenum contained in molybdic oxide leached | |
| Arsenic | 16.100 | 7.182 |
| Lead | 3.244 | 1.506 |
| Nickel | 6.371 | 4.286 |
| Selenium | 9.499 | 4.286 |
| Molybdenum | [Reserved] | [Reserved] |
| Ammonia (as N) | 1,544.000 | 678.800 |
| Fluoride | 405.400 | 230.500 |
(d) Hydrogen reduction furnace scrubber.
BAT Limitations for the Primary Molybdenum and Rhenium Subcategory
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
| | mg/kg (pounds per/million pounds) of molybdenum metal powder produced | |
| Arsenic | 3.183 | 1.420 |
| Lead | 0.641 | 0.298 |
| Nickel | 1.260 | 0.847 |
| Selenium | 1.878 | 0.847 |
| Molybdenum | [Reserved] | [Reserved]. |
| Ammonia (as N) | 305.300 | 134.200 |
| Fluoride | 80.150 | 45.570 |
(e) Depleted rhenium scrubbing solution.
BAT Limitations for the Primary Molybdenum and Rhenium Subcategory
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
| | mg/kg (pounds per/million pounds) of molybdenum sulfide roasted | |
| Arsenic | 0.995 | 0.444 |
| Lead | 0.201 | 0.093 |
| Nickel | 0.394 | 0.265 |
| Selenium | 0.587 | 0.265 |
| Molybdenum | [Reserved] | [Reserved]. |
| Ammonia (as N) | 95.440 | 41.960 |
| Fluoride | 25.060 | 14.250 |
[50 FR 38355, Sept. 20, 1985, as amended at 55 FR 31701, 31702, Aug. 3, 1990]