{"data":{"id":"us/40-cfr-421.113","jurisdiction":"us","citation":"40 CFR 421.113","heading":"Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.","body":"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:\n(a) Subpart K—Concentrate Digestion Wet Air Pollution Control.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of concentrate digested\nLead .174 .081\nZinc .635 .261\nAmmonia (as N) 82.910 36.450\nFluoride 21.770 12.440\n(b) Subpart K—Solvent Extraction Raffinate.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/Kg (pounds per million pounds) of concentrate digested\nLead 2.592 1.203\nZinc 9.442 3.888\nAmmonia (as N) 1,233.000 542.5000\nFluoride 324.000 185.100\n(c) Subpart K—Solvent Extraction Wet Air Pollution Control.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of concentrate digested\nLead .069 .032\nZinc .251 .103\nAmmonia (as N) 32.790 14.420\nFluoride 8.610 4.920\n(d) Subpart K—Precipitation and Filtration.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of concentrate digested\nLead 3.833 1.780\nZinc 13.960 5.750\nAmmonia (as N) 1,825.000 802.200\nFluoride 479.100 273.800\n(e) Subpart K—Precipitation and Filtration Wet Air Pollution Control.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of concentrate digested\nLead 1.778 .826\nZinc 6.478 2.668\nAmmonia (as N) 846.600 372.200\nFluoride 222.300 127.000\n(f) Subpart K—Tantalum Salt Drying.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of tantalum salt dried\nLead 16.950 7.871\nZinc 61.750 25.430\nAmmonia (as N) 8,070.000 3,548.000\nFluoride 2,119.000 1,211.000\n(g) Subpart K—Oxides Calcining Wet Air Pollution Control.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of columbium-tantalum oxide\nLead 1.076 .500\nZinc 3.919 1.614\nAmmonia (as N) 512.200 225.200\nFluoride 134.500 76.840\n(h) Subpart K—Reduction of Tantalum Salt to Metal.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of tantalum salt reduced\nLead 46.500 21.590\nZinc 169.400 69.750\nAmmonia (as N) 22,140.000 9,732.000\nFluoride 5,813.000 3,322.000\n(i) Subpart K—Reduction of Tantalum Salt to Metal Wet Air Pollution Control.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of tantalum salt reduced\nLead .572 .266\nZinc 2.084 .858\nFluoride 71.510 40.860\n(j) Subpart K—Tantalum Powder Wash.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of tantalum powder washed\nLead 5.721 2.656\nZinc 20.840 8.582\nAmmonia (as N) 2,724.000 1,198.000\nFluoride 715.200 408.700\n(k) Subpart K—Consolidation and Casting Contact Cooling.\nBAT Effluent Limitations\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of columbium or tantalum cast or consolidated\nLead .000 .000\nZinc .000 .000\nAmmonia (as N) .000 .000\nFluoride .000 .000","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER N—EFFLUENT GUIDELINES AND STANDARDS","PART 421—NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY","Subpart K—Primary Columbium-Tantalum 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":"fe88a2f302ed1ca19359e0039baf5d90b4392eef0d330db47e20b8aaf5b9ae14","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-421.112","next":"us/40-cfr-421.114"},"notice":"GroundRules: Original legal text. Not legal advice."}