Pretreatment standards for new sources.

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§ 421.256 Pretreatment standards for new sources.

Except as provided in 40 CFR 403.7, any new 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 new sources. The mass of wastewater pollutants in primary precious metals and mercury process wastewater introduced into a POTW shall not exceed the following values:

(a) Smelter wet air pollution control.

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PSNS 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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PSNS 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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PSNS 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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PSNS 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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PSNS 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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PSNS 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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PSNS 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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PSNS 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 5.656
Gold 1.380

(i) Mercury cleaning bath water.

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PSNS 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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