Regulations last checked for updates: May 19, 2024

Title 40 - Protection of Environment last revised: May 16, 2024
§ 421.195 - Pretreatment standards for existing sources.

Except as provided in 40 CFR 403.7 and 403.13, any existing source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for existing sources. The mass of wastewater pollutants in secondary indium process wastewater introduced into a POTW must not exceed the following values:

(a) Displacement Supernatant.

PSES for the Secondary Indium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of indium metal produced
Cadmium2.1050.929
Lead2.6001.238
Zinc9.0373.776
Indium2.7241.114

(b) Spent Electrolyte.

PSES for the Secondary Indium Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of cathode indium produced
Cadmium12.1705.370
Lead15.0407.160
Zinc52.27021.840
Indium15.7506.444
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,c,e,and, 1316 (b) andc, 1317 (b) andc,1318; 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217; 101 Stat. 7, Pub. L. 100-4
source: 49 FR 8790, Mar. 8, 1984, unless otherwise noted.
cite as: 40 CFR 421.195