{"data":{"id":"us/40-cfr-421.116","jurisdiction":"us","citation":"40 CFR 421.116","heading":"Pretreatment standards for new sources.","body":"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 columbium-tantalum process wastewater introduced into a POTW shall not exceed the following values:\n(a) Subpart K—Concentrate Digestion Wet Air Pollution Control.\nPSNS\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.\nPSNS\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.\nPSNS\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.\nPSNS\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.\nPSNS\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.\nPSNS\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.\nPSNS\nPollutant or pollutant property Maximum for any 1 day Maximum for monthly average\nmg/kg (pounds per million pounds) of columbium-tantalum oxide dried\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.\nPSNS\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.\nPSNS\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\nAmmonia (as N) 272.400 119.700\nFluoride 71.510 40.860\n(j) Subpart K—Tantalum Powder Wash.\nPSNS\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.\nPSNS\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":"50ed6a700753d01739de657c4ea7f836a82fe1aff2d1d1252a317f71a9d448f5","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-421.115","next":"us/40-cfr-421.117"},"notice":"GroundRules: Original legal text. Not legal advice."}