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. 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. 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. 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. 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 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. 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. 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. 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. 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. 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. 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. 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. 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. 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. 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]