40 CFR § 421.114 - Standards of performance for new sources.

---
identifier: "/us/cfr/t40/s421.114"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 421.114 - Standards of performance for new sources."
title_number: 40
title_name: "Protection of Environment"
section_number: "421.114"
section_name: "Standards of performance for new sources."
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"
---


# 421.114 Standards of performance for new sources.

Any new source subject to this subpart shall achieve the following new source performance standards:

(a) Subpart K—Concentrate Digestion Wet Air Pollution Control.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of concentrate digested |  |
| Lead | .174 | .081 |
| Zinc | .635 | .261 |
| Ammonia (as N) | 82.910 | 36.450 |
| Fluoride | 21.770 | 12.440 |
| Total suspended solids | 9.330 | 7.464 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(b) Subpart K—Solvent Extraction Raffinate.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of concentrate digested |  |
| Lead | 2.592 | 1.203 |
| Zinc | 9.442 | 3.888 |
| Ammonia (as N) | 1,233.000 | 542.5000 |
| Fluoride | 324.000 | 185.100 |
| Total Suspended Solids | 138.900 | 111.100 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(c) Subpart K—Solvent Extraction Wet Air Pollution Control.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of concentrate digested |  |
| Lead | .069 | .032 |
| Zinc | .251 | .103 |
| Ammonia (as N) | 32.790 | 14.420 |
| Fluoride | 8.610 | 4.920 |
| Total suspended solids | 3.690 | 2.952 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(d) Subpart K—Precipitation and Filtration.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of concentrate digested |  |
| Lead | 3.833 | 1.780 |
| Zinc | 13.960 | 5.750 |
| Ammonia (as N) | 1,825.000 | 802.200 |
| Fluoride | 479.100 | 273.800 |
| Total suspended solids | 205.400 | 164.300 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(e) Subpart K—Precipitation and Filtration Wet Air Pollution Control.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of concentrate digested |  |
| Lead | 1.778 | .826 |
| Zinc | 6.478 | 2.668 |
| Ammonia (as N) | 846.600 | 372.200 |
| Fluoride | 222.300 | 127.000 |
| Total suspended solids | 95.270 | 76.210 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(f) Subpart K—Tantalum Salt Drying.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of tantalum salt dried |  |
| Lead | 16.950 | 7.871 |
| Zinc | 61.750 | 25.430 |
| Ammonia (as N) | 8,070.000 | 3,548.000 |
| Fluoride | 2,119.000 | 1,211.000 |
| Total suspended solids | 908.200 | 726.500 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(g) Subpart K—Oxides Calcining Wet Air Pollution Control.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of columbium-tantalum oxide dried |  |
| Lead | 1.076 | .500 |
| Zinc | 3.919 | 1.614 |
| Ammonia (as N) | 512.200 | 225.200 |
| Fluoride | 134.500 | 76.840 |
| Total suspended solids | 57.630 | 46.110 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(h) Subpart K—Reduction of Tantalum Salt to Metal.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of tantalum salt reduced |  |
| Lead | 46.500 | 21.590 |
| Zinc | 169.400 | 69.750 |
| Ammonia (as N) | 22,140.000 | 9,732.000 |
| Fluoride | 5,813.000 | 3,322.000 |
| Total suspended solids | 2,491.000 | 1,993.000 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(i) Subpart K—Reduction of Tantalum Salt to Metal Wet Air Pollution Control.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of tantalum salt reduced |  |
| Lead | .572 | .266 |
| Zinc | 2.084 | .858 |
| Ammonia (as N) | 272.400 | 119.700 |
| Fluoride | 71.510 | 40.860 |
| Total suspended solids | 30.650 | 24.520 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(j) Subpart K—Tantalum Powder Wash.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of tantalum powder washed |  |
| Lead | 5.721 | 2.656 |
| Zinc | 20.840 | 8.582 |
| Ammonia (as N) | 2,724.000 | 1,198.000 |
| Fluoride | 715.200 | 408.700 |
| Total suspended solids | 306.500 | 245.200 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

(k) Subpart K—Consolidation and Casting Contact Cooling.

NSPS

| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
| --- | --- | --- |
|  | mg/kg (pounds per million pounds) of columbium or tantalum cast or consolidated |  |
| Lead | .000 | .000 |
| Zinc | .000 | .000 |
| Ammonia (as N) | .000 | .000 |
| Fluoride | .000 | .000 |
| Total suspended solids | .000 | .000 |
| pH | () | () |
| Within the range of 7.5 to 10.0 at all times. |  |  |

[49 FR 8817, Mar. 8, 1984, as amended at 49 FR 29795, July 24, 1984; 50 FR 12253, Mar. 28, 1985]