{"data":{"id":"us/40-cfr-461.71","jurisdiction":"us","citation":"40 CFR 461.71","heading":"Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).","body":"(a) Except as provided in 40 CFR 125.30 through 125.32, any existing point source subject to this subpart must achieve the following effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available:\n(1) Subpart G—Wet Amalgamated Powder Anodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of Zinc\nEnglish units—pounds per 1,000,000 pounds of Zinc\nChromium 1.67 0.68\nMercury 0.95 0.38\nSilver 1.56 0.65\nZinc 5.55 2.32\nManganese 2.58 1.10\nOil and grease 76.0 45.6\nTSS 155.8 74.1\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(2) Subpart G—Gelled Amalgam Anodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of Zinc\nEnglish units—pounds per 1,000,000 pounds of Zinc\nChromium 0.30 0.12\nMercury 0.17 0.07\nSilver 0.28 0.12\nZinc 0.99 0.42\nManganese 0.46 0.20\nOil and grease 13.6 8.16\nTSS 27.9 13.26\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(3) Subpart G—Zinc Oxide, Formed Anodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of Zinc\nEnglish units—pounds per 1,000,000 pounds of Zinc\nChromium 62.9 25.7\nMercury 35.8 14.3\nSilver 58.7 24.3\nZinc 208.8 87.2\nManganese 97.2 41.5\nOil and grease 2,860.0 1,716.0\nTSS 5,863.0 2,789.0\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(4) Subpart G—Electrodeposited Anodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of zinc deposited\nEnglish units—pounds per 1,000,000 pounds of zinc deposited\nChromium 1,404.0 574.0\nMercury 798.0 319.0\nSilver 1,308.0 543.0\nZinc 4,657.0 1,946.0\nManganese 2,169.0 925.0\nOil and grease 63,800.0 38,280.0\nTSS 130,700.0 62,210.0\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(5) Subpart G—Silver Powder, Formed Cathodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of silver applied\nEnglish units—pounds per 1,000,000 pounds of silver applied\nChromium 86.2 35.3\nMercury 49.0 19.6\nSilver 80.4 33.3\nZinc 286.2 119.6\nManganese 133.3 56.8\nOil and grease 3,920.0 2,350.0\nTSS 8,036.0 3,822.0\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(6) Subpart G—Silver Oxide Powder, Formed Cathodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of silver applied\nEnglish units—pounds per 1,000,000 pounds of silver applied\nChromium 57.7 23.6\nMercury 32.8 13.1\nSilver 53.7 22.3\nZinc 191.3 79.9\nManganese 89.1 38.0\nOil and grease 2,620.0 1,570.0\nTSS 5,370.0 2,554.0\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(7) Subpart G—Silver Peroxide Cathodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of silver applied\nEnglish units—pounds per 1,000,000 pounds of silver applied\nChromium 13.8 5.65\nMercury 7.85 3.14\nSilver 12.9 5.34\nZinc 45.8 19.2\nManganese 21.4 9.11\nOil and grease 628.0 377.0\nTSS 1,287.0 612.0\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(8) Subpart G—Nickel Impregnated Cathodes.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of nickel applied\nEnglish units—pounds per 1,000,000 pounds of nickel applied\nChromium 721.6 295.2\nMercury 410.0 164.0\nNickel 3,149.0 2,083.0\nSilver 672.4 279.0\nZinc 2,394.4 1,000.4\nManganese 1,115.2 475.6\nOil and grease 32,800.0 19,680.0\nTSS 67,240.0 31,980.0\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(9) Subpart G—Miscellaneous Wastewater Streams.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of cells produced\nEnglish units—pounds per 1,000,000 pounds of cells produced\nChromium 3.85 1.58\nCyanide 2.54 1.05\nMercury 2.19 0.88\nNickel 16.82 11.12\nSilver 3.59 1.49\nZinc 12.79 5.34\nManganese 5.96 2.54\nOil and grease 175.20 105.12\nTSS 359.16 170.82\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(10) Subpart G—Silver Etch.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of silver processed\nEnglish units—pounds per 1,000,000 pounds of silver processed\nChromium 21.6 8.84\nMercury 12.3 4.91\nSilver 20.2 8.35\nZinc 71.7 30.0\nManganese 33.4 14.3\nOil and grease 982.0 589.2\nTSS 2,013.1 957.5\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(11) Subpart G—Silver Peroxide Production.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of silver peroxide processed\nEnglish units—pounds per 1,000,000 pounds of silver peroxide processed\nChromium 23.0 9.40\nMercury 13.1 5.22\nSilver 21.4 8.88\nZinc 76.2 31.80\nManganese 35.5 15.10\nOil and grease 1,044.0 627.00\nTSS 2,140.0 1,018.00\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(12) Subpart G—Silver Powder Production.\nBPT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nMetric units—mg/kg of silver powder processed\nEnglish units—pounds per 1,000,000 pounds of silver powder processed\nChromium 9.33 3.82\nMercury 5.30 2.12\nSilver 8.69 3.61\nZinc 30.95 12.93\nManganese 14.42 6.15\nOil and grease 424.0 254.40\nTSS 869.0 413.40\npH (1) (1)\n1 Within the range of 7.5-10.0 at all times.\n(b) There shall be no discharge allowance for process wastewater pollutants from any battery manufacturing operation other than those battery manufacturing operations listed above.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER N—EFFLUENT GUIDELINES AND STANDARDS","PART 461—BATTERY MANUFACTURING POINT SOURCE CATEGORY","Subpart G—Zinc Subcategory"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"98902e9ba5f2eb8d7365a73394565954ef54f447c12d02281d9f0b37bd12679c","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-461.70","next":"us/40-cfr-461.72"},"notice":"GroundRules: Original legal text. Not legal advice."}