40 CFR 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.