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
June 9, 2020
CFR

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

Open Table
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)

1Within 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

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

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

BPT Effluent Limitations

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

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

BPT Effluent Limitations

Open Table
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)

1Within 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

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

(f) Subpart L—Electrolytic Refining.

BPT Effluent Limitations

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

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

BPT Effluent Limitations

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

(h) Subpart L—Leaching.

BPT Effluent Limitations

Open Table
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)

1Within 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

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

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

BPT Effluent Limitations

Open Table
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)

1Within the range of 7.5 to 10.0 at all times.

(k) Subpart L—Floor and Equipment Washdown.

BPT Effluent Limitations

Open Table
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)

1Within 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]


Tried the LawStack mobile app?

Join thousands and try LawStack mobile for FREE today.

  • Carry the law offline, wherever you go.
  • Download CFR, USC, rules, and state law to your mobile device.