40 CFR § 437.23 - Effluent limitations attainable by the application of the best available technology economically achievable (BAT).
---
identifier: "/us/cfr/t40/s437.23"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 437.23 - Effluent limitations attainable by the application of the best available technology economically achievable (BAT)."
title_number: 40
title_name: "Protection of Environment"
section_number: "437.23"
section_name: "Effluent limitations attainable by the application of the best available technology economically achievable (BAT)."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "N"
subchapter_name: "EFFLUENT GUIDELINES AND STANDARDS"
part_number: "437"
part_name: "THE CENTRALIZED WASTE TREATMENT POINT SOURCE CATEGORY"
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, 1316, 1317, 1318, 1342, and 1361."
regulatory_source: "65 FR 81300, Dec. 22, 2000, unless otherwise noted."
cfr_part: "437"
---
# 437.23 Effluent limitations attainable by the application of the best available technology economically achievable (BAT).
Except as provided in 40 CFR 125.30 through 125.32 or § 437.20(b), any existing point source subject to this subpart must achieve the following effluent limitations by the application of BAT: Limitations for arsenic, cadmium, chromium, cobalt, copper, lead, mercury, tin, zinc, butylbenzyl phthalate, carbazole, n-decane, bis(2-ethylhexyl) phthalate, fluoranthene, and n-octadecane are the same as the corresponding limitation specified in § 437.21.
[65 FR 81300, Dec. 22, 2000, as amended at 68 FR 71023, Dec. 22, 2003]