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Secs. 301, 304 (b), (c), (e), and (g), 306 (b) and (c), 307 (b) and (c), 308 and 501 of the Clean Water Act (the Federal Water Pollution Control Act Amendments of 1972, as amended by the Clean Water Act of 1977) and the Water Quality Act of 1987 (the “Act”); 33 U.S.C. 1311, 1314 (b), (c), (e), and (g), 1316 (b) and (c), 1317 (b) and (c), 1318 and 1361; 86 Stat. 816, Pub. L. 92-500; 91 Stat. 1567, Pub. L. 95-217; 101 Stat. 7, Pub. L. 100-4.
49 FR 8790, Mar. 8, 1984, unless otherwise noted.
50 FR 38361, Sept. 20, 1985, unless otherwise noted.
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Subscribe to: 40 CFR Part 421 Subpart W
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50 FR 38361, Sept. 20, 1985, unless otherwise noted.
The provisions of this subpart are applicable to discharges resulting from the production of gold, silver, or mercury by primary precious metals and mercury facilities.
For the purpose of this subpart the general definitions, abbreviations, and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.
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) Smelter wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold and silver smelted | ||
| Lead | 0.546 | 0.260 |
| Mercury | 0.325 | 0.130 |
| Silver | 0.533 | 0.221 |
| Zinc | 1.898 | 0.793 |
| Gold | 0.130 | |
| Oil and grease | 26.000 | 15.600 |
| Total suspended solids | 53.300 | 25.350 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(b) Silver chloride reduction spent solution.
| Pollutant of pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver reduced in solution | ||
| Lead | 0.168 | 0.080 |
| Mercury | 0.100 | 0.040 |
| Silver | 0.164 | 0.068 |
| Zinc | 0.584 | 0.244 |
| Gold | 0.040 | |
| Oil and grease | 8.000 | 4.800 |
| Total suspended solids | 16.400 | 7.800 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(c) Electrolytic cells wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold refined electrolytically | ||
| Lead | 83.160 | 39.600 |
| Mercury | 49.500 | 19.800 |
| Silver | 81.180 | 33.660 |
| Zinc | 289.100 | 120.800 |
| Gold | 19.800 | |
| Oil and grease | 3,960.000 | 2,376.000 |
| Total suspended solids | 8,118.000 | 3,861.000 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(d) Electrolyte preparation wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver in electrolyte produced | ||
| Lead | 0.021 | 0.010 |
| Mercury | 0.013 | 0.005 |
| Silver | 0.021 | 0.009 |
| Zinc | 0.073 | 0.031 |
| Gold | 0.005 | |
| Oil and Grease | 1.000 | 0.600 |
| Total suspended solids | 2.050 | 0.975 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(e) Calciner wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 78.200 | 37.240 |
| Mercury | 46.550 | 18.620 |
| Silver | 76.340 | 31.650 |
| Zinc | 271.900 | 113.600 |
| Gold | 18.600 | |
| Oil and Grease | 3,724.000 | 2,234.000 |
| Total suspended solids | 7,634.000 | 3,631.000 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(f) Calcine quench water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 7.392 | 3.520 |
| Mercury | 4.400 | 1.760 |
| Silver | 7.216 | 2.992 |
| Zinc | 25.700 | 10.740 |
| Gold | 1.760 | |
| Oil and Grease | 352.000 | 211.200 |
| Total suspended solids | 721.600 | 343.200 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(g) Calciner stack gas contact cooling water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 1.743 | 0.830 |
| Mercury | 1.038 | 0.415 |
| Silver | 1.702 | 0.706 |
| Zinc | 6.059 | 2.532 |
| Gold | 0.415 | |
| Oil and Grease | 83.000 | 49.800 |
| Total suspended solids | 170.200 | 80.930 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(h) Condenser blowdown.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 5.796 | 2.760 |
| Mercury | 3.450 | 1.380 |
| Silver | 5.658 | 2.346 |
| Zinc | 20.150 | 8.418 |
| Gold | 1.380 | |
| Oil and Grease | 276.000 | 165.600 |
| Total suspended solids | 565.800 | 269.100 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(i) Mercury cleaning bath water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 0.588 | 0.280 |
| Mercury | 0.350 | 0.140 |
| Silver | 0.574 | 0.238 |
| Zinc | 2.044 | 0.854 |
| Gold | 0.140 | |
| Oil and Grease | 28.000 | 16.800 |
| Total suspended solids | 57.400 | 27.300 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
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 available technology economically achievable:
(a) Smelter wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold and silver smelted | ||
| Lead | 0.364 | 0.169 |
| Mercury | 0.195 | 0.078 |
| Silver | 0.377 | 0.156 |
| Zinc | 1.326 | 0.546 |
| Gold | 0.130 | |
(b) Silver chloride reduction spent solution.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver reduced in solution | ||
| Lead | 0.112 | 0.052 |
| Mercury | 0.060 | 0.024 |
| Silver | 0.116 | 0.048 |
| Zinc | 0.408 | 0.168 |
| Gold | 0.040 | |
(c) Electrolytic cells wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold refined electrolytically | ||
| Lead | 5.544 | 2.574 |
| Mercury | 2.970 | 1.188 |
| Silver | 5.742 | 2.376 |
| Zinc | 20.200 | 8.316 |
| Gold | 1.980 | |
(d) Electrolyte preparation wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver in electrolyte produced | ||
| Lead | 0.014 | 0.007 |
| Mercury | 0.008 | 0.003 |
| Silver | 0.015 | 0.006 |
| Zinc | 0.051 | 0.021 |
| Gold | 0.005 | |
(e) Calciner Wet Air Pollution Control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 6.160 | 2.860 |
| Mercury | 3.300 | 1.320 |
| Silver | 6.380 | 2.640 |
| Zinc | 22.440 | 9.240 |
| Gold | 2.200 | |
(f) Calcine quench water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 4.928 | 2.288 |
| Mercury | 2.640 | 1.056 |
| Silver | 5.104 | 2.112 |
| Zinc | 17.950 | 7.392 |
| Gold | 1.760 | |
(g) Calciner stack gas contact cooling water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 1.162 | 0.540 |
| Mercury | 0.623 | 0.249 |
| Silver | 1.204 | 0.498 |
| Zinc | 4.233 | 1.743 |
| Gold | 0.415 | |
(h) Condenser blowdown.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 3.864 | 1.794 |
| Mercury | 2.070 | 0.828 |
| Silver | 4.002 | 1.656 |
| Zinc | 14.080 | 5.796 |
| Gold | 1.380 | |
(i) Mercury cleaning bath water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 0.392 | 0.182 |
| Mercury | 0.210 | 0.084 |
| Silver | 0.406 | 0.168 |
| Zinc | 1.428 | 0.588 |
| Gold | 0.140 | |
Any new source subject to this subpart shall achieve the following new source performance standards:
(a) Smelter wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold and silver smelted | ||
| Lead | 0.364 | 0.169 |
| Mercury | 0.195 | 0.078 |
| Silver | 0.377 | 0.156 |
| Zinc | 1.326 | 0.546 |
| Gold | 0.130 | |
| Oil and Grease | 13.000 | 13.000 |
| Total suspended solids | 19.500 | 15.600 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(b) Silver chloride reduction spent solution.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver reduced in solution | ||
| Lead | 0.112 | 0.052 |
| Mercury | 0.060 | 0.024 |
| Silver | 0.116 | 0.048 |
| Zinc | 0.408 | 0.168 |
| Gold | 0.040 | |
| Oil and Grease | 4.000 | 4.000 |
| Total suspended solids | 6.000 | 4.800 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(c) Electrolytic cells wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold refined electrolytically | ||
| Lead | 5.544 | 2.574 |
| Mercury | 2.970 | 1.188 |
| Silver | 5.742 | 2.376 |
| Zinc | 20.200 | 8.316 |
| Gold | 1.980 | |
| Oil and Grease | 198.000 | 198.000 |
| Total suspended solids | 297.000 | 237.600 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(d) Electrolyte preparation wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver in electrolyte produced | ||
| Lead | 0.014 | 0.007 |
| Mercury | 0.008 | 0.003 |
| Silver | 0.015 | 0.006 |
| Zinc | 0.051 | 0.021 |
| Gold | 0.005 | |
| Oil and Grease | 0.500 | 0.500 |
| Total suspended solids | 0.750 | 0.600 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(e) Calciner wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 6.160 | 2.860 |
| Mercury | 3.300 | 1.320 |
| Silver | 6.380 | 2.640 |
| Zinc | 22.440 | 9.240 |
| Gold | 2.200 | |
| Oil and Grease | 220.000 | 220.000 |
| Total suspended solids | 330.000 | 264.000 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(f) Calcine quench water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 4.928 | 2.288 |
| Mercury | 2.640 | 1.056 |
| Silver | 5.104 | 2.112 |
| Zinc | 17.950 | 7.392 |
| Gold | 1.760 | |
| Oil and Grease | 176.000 | 176.000 |
| Total suspended solids | 264.000 | 211.200 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(g) Calciner stack gas contract cooling water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) or mercury condensed | ||
| Lead | 1.162 | 0.540 |
| Mercury | 0.623 | 0.249 |
| Silver | 1.204 | 0.498 |
| Zinc | 4.233 | 1.743 |
| Gold | 0.415 | |
| Oil and Grease | 41.500 | 41.500 |
| Total suspended solids | 62.250 | 49.800 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(h) Condenser blowdown.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 3.864 | 1.794 |
| Mercury | 2.070 | 0.828 |
| Silver | 4.002 | 1.656 |
| Zinc | 14.080 | 5.796 |
| Gold | 1.380 | |
| Oil and Grease | 138.000 | 138.000 |
| Total suspended solids | 207.000 | 165.600 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
(i) Mercury cleaning bath water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of Mercury condensed | ||
| Lead | 0.392 | 0.182 |
| Mercury | 0.210 | 0.084 |
| Silver | 0.406 | 0.168 |
| Zinc | 1.428 | 0.588 |
| Gold | 0.140 | |
| Oil and Grease | 14.000 | 14.000 |
| Total suspended solids | 21.000 | 16.800 |
| pH | (1) | (1) |
| 1 Within the range of 7.5 to 10.0 at all times. | ||
[50 FR 38361, Sept. 20, 1985; 50 FR 41144, Oct. 9, 1985]
Except as provided in 40 CFR 403.7, any new source subject to this subpart which introduces pollutants into a publicly owned treatment works must comply with 40 CFR part 403 and achieve the following pretreatment standards for new sources. The mass of wastewater pollutants in primary precious metals and mercury process wastewater introduced into a POTW shall not exceed the following values:
(a) Smelter wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold and silver smelted | ||
| Lead | 0.364 | 0.169 |
| Mercury | 0.195 | 0.078 |
| Silver | 0.377 | 0.156 |
| Zinc | 1.326 | 0.546 |
| Gold | 0.130 | |
(b) Silver chloride reduction spent solution.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver reduced in solution | ||
| Lead | 0.112 | 0.052 |
| Mercury | 0.060 | 0.024 |
| Silver | 0.116 | 0.048 |
| Zinc | 0.408 | 0.168 |
| Gold | 0.040 | |
(c) Electrolytic cells wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of gold refined electrolytically | ||
| Lead | 5.544 | 2.574 |
| Mercury | 2.970 | 1.188 |
| Silver | 5.742 | 2.376 |
| Zinc | 20.200 | 8.316 |
| Gold | 1.980 | |
(d) Electrolyte preparation wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/troy ounce of silver in electrolyte produced | ||
| Lead | 0.014 | 0.007 |
| Mercury | 0.008 | 0.003 |
| Silver | 0.015 | 0.006 |
| Zinc | 0.051 | 0.021 |
| Gold | 0.005 | |
(e) Calciner wet air pollution control.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 6.160 | 2.860 |
| Mercury | 3.300 | 1.320 |
| Silver | 6.380 | 2.640 |
| Zinc | 22.440 | 9.240 |
| Gold | 2.200 | |
(f) Calcine quench water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 4.928 | 2.288 |
| Mercury | 2.640 | 1.056 |
| Silver | 5.104 | 2.112 |
| Zinc | 17.950 | 7.392 |
| Gold | 1.760 | |
(g) Calciner stack gas contact cooling water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 1.162 | 0.540 |
| Mercury | 0.623 | 0.249 |
| Silver | 1.204 | 0.498 |
| Zinc | 4.233 | 1,743 |
| Gold | 0.415 | |
(h) Condenser blowdown.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 3.864 | 1.794 |
| Mercury | 2.070 | 0.828 |
| Silver | 4.002 | 1.656 |
| Zinc | 14.080 | 5.656 |
| Gold | 1.380 | |
(i) Mercury cleaning bath water.
| Pollutant or pollutant property | Maximum for any 1 day | Maximum for monthly average |
|---|---|---|
| mg/kg (pounds per million pounds) of mercury condensed | ||
| Lead | 0.392 | 0.182 |
| Mercury | 0.210 | 0.084 |
| Silver | 0.406 | 0.168 |
| Zinc | 1.428 | 0.588 |
| Gold | 0.140 | |