Regulations last checked for updates: May 18, 2024

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

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

(a) Rolling spent emulsions.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium rolled with emulsions
Chromium0.0330.014
Zinc0.1090.046
Ammonia9.954.37
Fluoride4.441.97

(b) Forging spent lubricants—subpart B—BAT. There shall be no discharge of process wastewater pollutants.

(c) Forging contact cooling water.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of forged magnesium cooled with water
Chromium0.1270.052
Zinc0.4220.177
Ammonia38.517.0
Fluoride17.27.63

(d) Forging equipment cleaning wastewater.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium forged
Chromium0.0020.0007
Zinc0.0060.003
Ammonia0.5320.234
Fluoride0.2380.106

(e) Direct chill casting contact cooling water.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium cast with direct chill methods
Chromium1.740.711
Zinc5.772.41
Ammonia527232
Fluoride235105

(f) Surface treatment spent baths.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium surface treated
Chromium0.2050.084
Zinc0.6810.285
Ammonia62.127.3
Fluoride27.812.3

(g) Surface treatment rinse.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium surface treated
Chromium0.8320.340
Zinc2.761.16
Ammonia252111
Fluoride11349.9

(h) Sawing or grinding spent emulsions.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium sawed or ground
Chromium0.0090.004
Zinc0.0290.012
Ammonia2.601.15
Fluoride1.160.515

(i) Degreasing spent solvents—subpart B—BAT. There shall be no discharge of process wastewater pollutants.

(j) Wet air pollution control scrubber blowdown.

Subpart B—BAT

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/off-kg (pounds per million off-pounds) of magnesium sanded and repaired or forged
Chromium0.2730.112
Zinc0.9040.378
Ammonia82.536.3
Fluoride36.916.4
authority: Secs. 301, 304(b), (c), (e), and (g), 306(b) and (c), 307, 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) (the “Act”); 33 U.S.C. 1311,1314,c,e,and, 1316(b) andc,and; 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217
source: 50 FR 34270, Aug. 23, 1985, unless otherwise noted.
cite as: 40 CFR 471.22