Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.

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§ 421.253 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) Smelter wet air pollution control.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold and silver smelted
Lead 0.364 0.169
Mercury 0.195 0.078
Silver 0.377 0.156
Zinc 1.326 0.546
Gold 0.130

(b) Silver chloride reduction spent solution.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver reduced in solution
Lead 0.112 0.052
Mercury 0.060 0.024
Silver 0.116 0.048
Zinc 0.408 0.168
Gold 0.040

(c) Electrolytic cells wet air pollution control.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold refined electrolytically
Lead 5.544 2.574
Mercury 2.970 1.188
Silver 5.742 2.376
Zinc 20.200 8.316
Gold 1.980

(d) Electrolyte preparation wet air pollution control.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver in electrolyte produced
Lead 0.014 0.007
Mercury 0.008 0.003
Silver 0.015 0.006
Zinc 0.051 0.021
Gold 0.005

(e) Calciner Wet Air Pollution Control.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of mercury condensed
Lead 6.160 2.860
Mercury 3.300 1.320
Silver 6.380 2.640
Zinc 22.440 9.240
Gold 2.200

(f) Calcine quench water.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of mercury condensed
Lead 4.928 2.288
Mercury 2.640 1.056
Silver 5.104 2.112
Zinc 17.950 7.392
Gold 1.760

(g) Calciner stack gas contact cooling water.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of mercury condensed
Lead 1.162 0.540
Mercury 0.623 0.249
Silver 1.204 0.498
Zinc 4.233 1.743
Gold 0.415

(h) Condenser blowdown.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of mercury condensed
Lead 3.864 1.794
Mercury 2.070 0.828
Silver 4.002 1.656
Zinc 14.080 5.796
Gold 1.380

(i) Mercury cleaning bath water.

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BAT Limitations for the Primary Precious Metals and Mercury Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of mercury condensed
Lead 0.392 0.182
Mercury 0.210 0.084
Silver 0.406 0.168
Zinc 1.428 0.588
Gold 0.140


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