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

  1. Law
  2. CFR 40
  3. Protection of Environment
  4. Environmental Protection Agency
  5. Effluent Guidelines and Standards
  6. Nonferrous Metals Manufacturing Point Source Category
  7. Secondary Precious Metals Subcategory
  8. Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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§ 421.262 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) Furnace wet air pollution control.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of precious metals, including silver, incinerated or smelted
Copper 136.400 71.800
Cyanide (total) 20.820 8.616
Zinc 104.800 43.800
Ammonia (as N) 9,571.000 4,207.000
Combined metals 21.54
Total suspended solids 2,944.000 1,400.000
pH (1) (1)

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

(b) Raw material granulation.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of precious metal in the granulated raw material
Copper 12.050 6.340
Cyanide (total) 1.839 0.761
Zinc 9.256 3.867
Ammonia (as N) 845.100 371.500
Combined metals 1.902
Total suspended solids 259.900 123.600
pH (1) (1)

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

(c) Spent plating solutions.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/liter of spent plating solution used as a raw material
Copper 1.900 1.000
Cyanide (total) 0.290 0.120
Zinc 1.460 0.610
Ammonia (as N) 133.300 58.600
Combined metals 0.300
Total suspended solids 41.000 19.500
pH (1) (1)

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

(d) Spent cyanide stripping solutions.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold produced by cyanide stripping
Copper 7.030 3.700
Cyanide (total) 1.073 0.444
Zinc 5.402 2.257
Ammonia (as N) 493.200 216.800
Combined metals 1.110
Total suspended solids 151.700 72.150
pH (1) (1)

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

(e) Refinery wet air pollution control.[2]

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of precious metals, including silver, produced in refinery
Copper 39.900 21.000
Cyanide (total) 6.090 2.520
Zinc 30.660 12.810
Ammonia (as N) 2,799.000 1,231.000
Combined metals 6.300
Total suspended solids 861.000 409.500
pH (1) (1)

1 Within the range of 7.5 to 10.0 at alltimes.

(f) Gold solvent extraction raffinate and wash water.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold produced by solvent extraction
Copper 1.197 0.630
Cyanide (total) 0.183 0.076
Zinc 0.920 0.384
Ammonia (as N) 83.980 36.920
Combined metals 0.189
Total suspended solids 25.830 12.290
pH (1) (1)

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

(g) Gold spent electrolyte.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold produced by electrolysis
Copper 0.017 0.009
Cyanide (total) 0.003 0.001
Zinc 0.103 0.005
Ammonia (as N) 1.160 0.510
Combined metals 0.003
Total suspended solids 0.357 0.170
pH (1) (1)

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

(h) Gold precipitation and filtration.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold precipitated
Copper 8.360 4.400
Cyanide (total) 1.276 0.528
Zinc 6.424 2.684
Ammonia (as N) 586.500 257.800
Combined metals 1.320
Total suspended solids 180.400 85.800
pH (1) (1)

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

(i) Platinum precipitation and filtration.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of platinum precipitated
Copper 9.880 5.200
Cyanide (total) 1.508 0.624
Zinc 7.592 3.172
Ammonia (as N) 693.200 304.700
Combined metals 1.560
Total suspended solids 213.200 101.400
pH (1) (1)

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

(j) Palladium precipitation and filtration.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of palladium precipitated
Copper 11.400 6.000
Cyanide (total) 1.740 0.720
Zinc 8.760 3.660
Ammonia (as N) 799.800 351.600
Combined metals 1.800
Total suspended solids 246.000 117.000
pH (1) (1)

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

(k) Other platinum group metals precipitation and filtration.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of other platinum group metals precipitated
Copper 9.880 5.200
Cyanide (total) 1.508 0.624
Zinc 7.592 3.172
Ammonia (as N) 693.200 304.700
Combined metals 1.560
Total suspended solids 213.200 101.400
pH (1) (1)

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

(l) Spent solution from PGC salt production.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of gold contained in PGC product
Copper 1.710 0.900
Cyanide (total) 0.261 0.108
Zinc 1.314 0.549
Ammonia (as N) 120.000 52.740
Combined metals 0.270
Total suspended solids 36.900 17.550
pH (1) (1)

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

(m) Equipment and floor wash.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of precious metals, including silver, produced in refinery
Copper 0.000 0.000
Cyanide (total) 0.000 0.000
Zinc 0.000 0.000
Ammonia (as N) 0.000 0.000
Combined metals 0.000 0.000
Total suspended solids 0.000 0.000
pH (1) (1)

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

(n) Preliminary treatment.

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BPT Limitations for the Secondary Precious Metals Subcategory

Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/troy ounce of total precious metals produced through this operation
Copper 95.000 50.000
Cyanide (Total) 14.500 6.000
Zinc 73.000 30.500
Ammonia (as N) 6665.000 2930.000
Combined Metals 15.000
Total Suspended Solids 2050.000 975.000
pH (1) (1)

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

[50 FR 38365, Sept. 20, 1985, as amended at 55 FR 31705, 31706, Aug. 3, 1990]

Footnotes - 421.262

[2] This allowance applies to either acid or alkaline wet air pollution control scrubbers. If both acid and alkaline wet air pollution control scrubbers are present in a particular facility the same allowance applies to each.


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