Regulations last checked for updates: May 19, 2024

Title 40 - Protection of Environment last revised: May 16, 2024
§ 421.293 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.

Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart shall achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best available technology economically achievable:

(a) Tin smelter SO2 scrubber.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of crude tapped tin produced
Arsenic12.7905.703
Lead2.5751.196
Iron11.0405.611
Tin3.4952.024

(b) Dealuminizing rinse.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of dealuminized scrap produced
Lead0.0100.005
Cyanide (total)0.0070.003
Fluoride1.2250.697
Tin0.0130.008

(c) Tin mud acid neutralization filtrate.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of neutralized dewatered tin mud produced
Lead1.4130.656
Cyanide (total)1.0090.404
Fluoride176.600100.400
Tin1.9181.110

(d) Tin hydroxide wash.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tin hydroxide washed
Lead3.3471.554
Cyanide (total)2.3910.956
Fluoride418.400237.900
Tin4.5422.630

(e) Spent electrowinning solution from new scrap.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of cathode tin produced
Lead4.7042.184
Cyanide (total)3.3601.344
Fluoride588.000334.300
Tin6.3843.696

(f) Spent electrowinning solution from municipal solid waste.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of MSW scrap used as raw material
Lead0.0330.015
Cyanide (total)0.0240.010
Fluoride4.1652.368
Tin0.0450.026

(g) Tin hydroxide supernatant from scrap.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tin metal recovered from scrap
Lead15.5807.233
Cyanide (total)11.1304.451
Fluoride1,947.0001,107.000
Tin21.14021.240

(h) Tin hydroxide supernatant from plating solutions and sludges.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tin metal recovered from plating solutions and sludges
Lead32.2014.95
Cyanide (total)23.009.20
Fluoride4,025.002,289.00
Tin43.7025.30

(i) Tin hydroxide filtrate.

BAT Limitations for the Secondary Tin Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of tin metal produced
Lead7.0123.256
Cyanide (total)5.0092.004
Fluoride876.500498.400
Tin9.5175.510
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 421.293