40 CFR § 420.74 - New source performance standards (NSPS).

---
identifier: "/us/cfr/t40/s420.74"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 420.74 - New source performance standards (NSPS)."
title_number: 40
title_name: "Protection of Environment"
section_number: "420.74"
section_name: "New source performance standards (NSPS)."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "N"
subchapter_name: "EFFLUENT GUIDELINES AND STANDARDS"
part_number: "420"
part_name: "IRON AND STEEL 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: "33 U.S.C. 1311, 1314, 1316, 1317, 1318, 1342, and 1361."
regulatory_source: "47 FR 23284, May 27, 1982, unless otherwise noted."
cfr_part: "420"
---


# 420.74 New source performance standards (NSPS).

The discharge of wastewater pollutants from any new source subject to this subpart shall not exceed the standards set forth below.

(a) *Primary mills, carbon and specialty*—(1) *Without scarfing.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of product |  |
| TSS | 0.0150 | 0.00563 |
| O&G | 0.00373 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0. |  |  |

(2) *With scarfing.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of product |  |
| TSS | 0.0234 | 0.00876 |
| O&G | 0.00584 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0. |  |  |

(b) *Section mills*—(1) *Carbon.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of product |  |
| TSS | 0.0334 | 0.0125 |
| O&G | 0.00834 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0. |  |  |

(2) *Specialty.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of product |  |
| TSS | 0.0217 | 0.00813 |
| O&G | 0.00542 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0. |  |  |

(c) *Flat mills*—(1) *Hot strip and sheet mills, carbon and specialty.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of products |  |
| TSS | 0.0435 | 0.0163 |
| O&G | 0.0109 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0 |  |  |

(2) *Carbon plate mills.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of products |  |
| TSS | 0.0234 | 0.00876 |
| O&G | 0.00584 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0 |  |  |

(3) *Specialty plate mills.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of products |  |
| TSS | 0.0100 | 0.00375 |
| O&G | 0.00250 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0 |  |  |

(d) *Pipe and tube mills, carbon and specialty.*

Subpart G

|  |  |  |
| --- | --- | --- |
|  | Kg/kkg (pounds per 1,000 lb) of products |  |
| TSS | 0.0369 | 0.0138 |
| O&G | 0.00917 |  |
| pH | () | () |
| Within the range of 6.0 to 9.0 |  |  |