Standards of performance for new sources.

  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. Standards of performance for new sources.

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§ 421.264 Standards of performance for new sources.

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

(a) Furnace wet air pollution control.

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NSPS 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 5.760 2.745
Cyanide (total) 0.900 0.360
Zinc 4.590 1.890
Combined metals 1.350
Ammonia (as N) 599.900 263.700
Total suspended solids 67.500 54.000
pH (1) (1)

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

(b) Raw material granulation.

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NSPS 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 in the granulated raw material
Copper 0.819 0.390
Cyanide (total) 0.128 0.051
Zinc 0.653 0.269
Combined metals 0.192
Ammonia (as N) 85.310 37.500
Total suspended solids 9.600 7.680
pH (1) (1)

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

(c) Spent plating solutions.

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NSPS 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 1.280 0.610
Cyanide (total) 0.200 0.080
Zinc 1.020 0.420
Combined metals 0.300
Ammonia (as N) 133.300 58.600
Total suspended solids 15.000 12.000
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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NSPS 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 4.736 2.257
Cyanide (total) 0.740 0.296
Zinc 3.774 1.554
Combined metals 1.11
Ammonia (as N) 493.200 216.800
Total suspended solids 55.500 44.400
pH (1) (1)

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

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

Expand Table

NSPS 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 1.280 0.610
Cyanide (total) 0.200 0.080
Zinc 1.020 0.420
Combined metals 0.300
Ammonia (as N) 133.300 58.600
Total suspended solids 15.000 12.000
pH (1) (1)

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

(f) Gold solvent extraction raffinate and wash water.

Expand Table

NSPS 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 0.806 0.384
Cyanide (total) 0.126 0.050
Zinc 0.643 0.265
Combined metals 0.189
Ammonia (as N) 83.980 36.920
Total suspended solids 9.450 7.560
pH (1) (1)

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

(g) Gold spent electrolyte.

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NSPS 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 0.011 0.005
Cyanide (total) 0.002 0.001
Combined metals 0.003
Zinc 0.009 0.004
Ammonia (as N) 1.160 0.510
Total suspended solids 0.131 0.104
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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NSPS 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 5.632 2.684
Cyanide (total) 0.880 0.352
Zinc 4.488 1.848
Combined metals 1.320
Ammonia (as N) 586.500 257.800
Total suspended solids 66.00 52.800
pH (1) (1)

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

(i) Platinum precipitation and filtration.

Expand Table

NSPS 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 6.656 3.172
Cyanide (total) 1.040 0.416
Zinc 5.304 2.184
Combined metals 1.560
Ammonia (as N) 693.200 304.700
Total suspended solids 78.000 62.400
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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NSPS 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 7.680 3.660
Cyanide (total) 1.200 0.480
Zinc 6.1200 2.520
Combined metals 1.800
Ammonia (as N) 799.800 351.600
Total suspended solids 90.000 72.000
pH (1) (1)

1 Within the range of 7.5 to 10.00 at all times.

(k) Other platinum group metals precipitation and filtration.

Expand Table

NSPS 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 6.656 3.172
Cyanide (total) 1.040 0.416
Zinc 5.304 2.184
Combined metals 1.560
Ammonia (as N) 693.200 304.700
Total suspended solids 78.000 62.400
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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NSPS 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 1.152 0.549
Cyanide (total) 0.180 0.072
Zinc 0.918 0.378
Combined metals 0.270
Ammonia (as N) 120.000 52.740
Total suspended solids 13.500 10.800
pH (1) (1)

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

(m) Equipment and floor wash.

Expand Table

NSPS 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
Combined metals 0.000
Ammonia (as N) 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.

Expand Table

NSPS 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 64.000 30.500
Cyanide (Total) 10.000 4.000
Zinc 51.000 21.000
Combined metals 15.000
Ammonia (as N) 6665.000 2930.000
Total Suspended Solids 750.000 600.000
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 31708, Aug. 3, 1990]

Footnotes - 421.264

[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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