40 CFR § 420.135 - Pretreatment standards for existing sources (PSES).

---
identifier: "/us/cfr/t40/s420.135"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 420.135 - Pretreatment standards for existing sources (PSES)."
title_number: 40
title_name: "Protection of Environment"
section_number: "420.135"
section_name: "Pretreatment standards for existing sources (PSES)."
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"
---


# 420.135 Pretreatment standards for existing sources (PSES).

Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart that introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and must achieve the following pretreatment standards for existing sources (PSES):

(a) *Direct-reduced iron.* [Reserved]

(b) *Forging operations.* [Reserved]

(c) *Briquetting.* There shall be no discharge of process wastewater pollutants to POTWs.