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Title 40

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Subpart L—Secondary Silver Subcategory

Source:

49 FR 8821, Mar. 8, 1984, unless otherwise noted.

§ 421.120 Applicability: Description of the secondary silver subcategory.

The provisions of this subpart are applicable to discharges resulting from the production of silver from secondary silver facilities processing photographic and nonphotographic raw materials.

[49 FR 8821, Mar. 8, 1984; 49 FR 26739, June 29, 1984]

§ 421.121 Specialized definitions.

For the purpose of this subpart the general definitions, abbreviations, and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

§ 421.122 Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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 practicable technology currently available:

(a) Subpart L—Film Stripping.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver from film stripping
Copper 95.670 50.350
Zinc 73.510 30.720
Ammonia (as N) 6,712.000 2,951.000
Total suspended solids 2,065.000 981.800
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(b) Subpart L—Film Stripping Wet Air Pollution Control and Precipitation and Filtration of Film Stripping Solutions Wet Air Pollution Control.

BPT Effluent Limitations

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 1.843 .970
Zinc 1.416 .592
Ammonia (as N) 129.300 56.840
Total suspended solids 39.770 18.920
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(c) Subpart L—Precipitation and Filtration of Film Stripping Solutions.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver precipitated
Copper 109.400 57.570
Zinc 84.050 35.120
Ammonia (as N) 7,674.000 3,374.000
Total suspended solids 2,361.000 1,123.000
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(d) Subpart L—Precipitation and Filtration of Photographic Solutions.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver precipitated
Copper 50.540 26.600
Zinc 38.836 16.226
Ammonia (as N) 3,545.000 1,559.000
Total suspended solids 1,090.600 518.700
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(e) Subpart L—Precipitation and Filtration of Photographic Solutions Wet Air Pollution Control.

BPT Effluent Limitations

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 23.070 12.140
Zinc 17.730 7.406
Ammonia (as N) 1,618.000 711.400
Total suspended solids 497.800 236.800
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(f) Subpart L—Electrolytic Refining.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver from electrolytic refining
Copper 1.444 .760
Zinc 1.110 .464
Ammonia (as N) 101.300 44.540
Total suspended solids 31.160 14.820
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(g) Subpart L—Furnace Wet Air Pollution Control.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver roasted, smelted, or dried
Copper 1.273 .670
Zinc .978 .409
Ammonia (as N) 89.310 39.260
Total suspended solids 27.470 13.070
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(h) Subpart L—Leaching.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver produced from leaching
Copper .164 .086
Zinc .126 .053
Ammonia (as N) 11.470 5.040
Total suspended solids 3.526 1.677
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(i) Subpart L—Leaching Wet Air Pollution Control and Precipitation of Nonphotographic Solutions Wet Air Pollution Control.

BPT Effluent Limitations

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 8.417 4.430
Zinc 6.468 2.703
Ammonia (as N) 590.500 259.600
Total suspended solids 181.700 86.390
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(j) Subpart L—Precipitation and Filtration of Nonphotographic Solutions.

BPT Effluent Limitations

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of silver precipitated
Copper 5.833 3.070
Zinc 4.482 1.873
Ammonia (as N) 409.300 179.900
Total suspended solids 125.900 59.870
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(k) Subpart L—Floor and Equipment Washdown.

BPT Effluent Limitations

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
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

[49 FR 8821, Mar. 8, 1984, as amended at 49 FR 29795, July 24, 1984]

§ 421.123 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) Subpart L—Film Stripping.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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.

BAT Effluent Limitations

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

§ 421.124 Standards of performance for new sources.

Any new source subject to this subpart shall achieve the following new source performance standards:

(a) Subpart L—Film Stripping.

NSPS

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
Total suspended solids 755.300 604.200
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(b) Subpart L—Film Stripping Wet Air Pollution Control and Precipitation and Filtration of Film Stripping Solutions Wet Air Pollution Control.

NSPS

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
Total suspended solids 14.550 11.640
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(c) Subpart L—Precipitation and Filtration of Film Stripping Solutions.

NSPS

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
Total suspended solids 863.600 690.900
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(d) Subpart L—Precipitation and Filtration of Photographic Solutions.

NSPS

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
Total suspended solids 399.000 319.200
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(e) Subpart L—Precipitation and Filtration of Photographic Solutions Wet Air Pollution Control.

NSPS

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
Total suspended solids 182.100 145.700
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(f) Subpart L—Electrolytic Refining.

NSPS

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
Total suspended solids 11.400 9.120
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(g) Subpart L—Furnace Wet Air Pollution Control.

NSPS

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
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(h) Subpart L—Leaching.

NSPS

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
Total suspended solids 1.290 1.032
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(i) Subpart L—Leaching Wet Air Pollution Control and Precipitation of Nonphotographic Solutions Wet Air Pollution Control.

NSPS

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
Total suspended solids 66.450 53.160
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(j) Subpart L—Precipitation and Filtration of Nonphotograhic Solutions.

NSPS

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
Total suspended solids 46.050 36.840
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

(k) Subpart L—Floor and Equipment Washdown.

NSPS

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
Total suspended solids .000 .000
pH (1) (1)
1 Within the range of 7.5 to 10.0 at all times.

[49 FR 8821, Mar. 8, 1984, as amended at 49 FR 29795, July 24, 1984]

§ 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

§ 421.126 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 secondary silver process wastewater introduced into a POTW shall not exceed the following values:

(a) Subpart L—Film Stripping.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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.

PSNS

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

[49 FR 8821, Mar. 8, 1984; 49 FR 26739, June 29, 1984]

§ 421.127 [Reserved]