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Code of Federal Regulations (Last Updated: July 5, 2024) |
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Title 40 - Protection of Environment |
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Chapter I - Environmental Protection Agency |
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SubChapter N - Effluent Guidelines and Standards |
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Part 421 - Nonferrous Metals Manufacturing Point Source Category |
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Subpart L - Secondary Silver Subcategory |
§ 421.125 - Pretreatment standards for existing sources.
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§ 421.125 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 silver process wastewater introduced into a POTW must not exceed the following values.
(a) Subpart L - Film Stripping.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver from film stripping Copper 64.450 30.720 Zinc 51.360 21.150 Ammonia (as N) 6,712.000 2,951.000 (b) Subpart L - Film Stripping Wet Air Pollution Control and Precipitation and Filtration of Film Stripping Solutions Wet Air Pollution Control.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver from precipitation and filtration of film stripping solutions Copper 1.242 .592 Zinc .990 .408 Ammonia (as N) 129.300 56.840 (c) Subpart L - Precipitation and Filtration of Film Stripping Solutions.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver precipitated Copper 73.690 35.120 Zinc 58.720 24.180 Ammonia (as N) 7,674.000 3,374.000 (d) Subpart L - Precipitation and Filtration of Photographic Solutions.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver precipitated Copper 34.048 16.226 Zinc 27.132 11.172 Ammonia (as N) 3,545.000 1,559.000 (e) Subpart L - Precipitation and Filtration of Photographic Solutions Wet Air Pollution Control.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver from precipitation and filtration of photographic solutions Copper 15.540 7.406 Zinc 12.380 5.099 Ammonia (as N) 1,618.000 711.400 (f) Subpart L - Electrolytic Refining.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver from electrolytic refining Copper .973 .464 Zinc .775 .319 Ammonia (as N) 101.300 44.540 (g) Subpart L - Furnace Wet Air Pollution Control.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver roasted, smelted, or dried Copper .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (h) Subpart L - Leaching.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver produced from leaching Copper .110 .053 Zinc .088 .036 Ammonia (as N) 11.470 5.040 (i) Subpart L - Leaching Wet Air Pollution Control and Precipitation of Nonphotographic Solutions Wet Air Pollution Control.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver produced from leaching or silver precipitated Copper 5.671 2.703 Zinc 4.519 1.861 Ammonia (as N) 590.500 259.600 (j) Subpart L - Precipitation and Filtration of Nonphotographic Solutions.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver precipitated Copper 3.930 1.873 Zinc 3.132 1.290 Ammonia (as N) 409.300 179.900 (k) Subpart L - Floor and Equipment Washdown.
PSES
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average mg/troy ounce of silver production Copper .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000