CFR > Title 40 - Protection of Environment > CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY > SUBCHAPTER N—EFFLUENT GUIDELINES AND STANDARDS (Parts 400–471) > PART 421—NONFERROUS METALS MANUFACTURING POINT SOURCE CATEGORY > SUBPART N—Primary Antimony Subcategory (§421.140 to §421.147) > 421.143—Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.

421.143—Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best available technology economically achievable.

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) Sodium Antimonate Autoclave Wastewater.
BAT Limitations for the Primary Antimony Subcategory
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of antimony contained in sodium antimonate product
Antimony 30.150 13.440
Arsenic 21.720 9.687
Mercury 2.344 0.937
(b) Fouled Anolyte.
BAT Limitations for the Primary Antimony Subcategory
Pollutant or pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg pounds per million pounds of antimony metal produced by electrowinning
Antimony 30.150 13.440
Arsenic 21.720 9.687
Mercury 2.344 0.937
(c) Cathode Antimony Wash Water
BAT Limitations for the Primary Antimony Subcategory
Pollutant of pollutant property Maximum for any 1 day Maximum for monthly average
mg/kg (pounds per million pounds) of antimony metal produced by electrowinning
Antimony 60.310 26.870
Arsenic 43.430 19.370
Mercury 4.687 1.875