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Code of Federal Regulations Title 40. Protection of Environment § 40.421.125 Pretreatment standards for existing sources

Current as of January 02, 2025 | Updated by Findlaw Staff

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
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Cite this article: FindLaw.com - Code of Federal Regulations Title 40. Protection of Environment § 40.421.125 Pretreatment standards for existing sources - last updated January 02, 2025 | https://codes.findlaw.com/cfr/title-40-protection-of-environment/cfr-sect-40-421-125/

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