40 CFR 421.142: Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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 control technology currently available:

(a) Sodium Antimonate Autoclave Wastewater.

BPT 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 44.840 20.000

Arsenic 32.650 14.530

Mercury 3.906 1.562

Total suspended solids 640.600 304.700

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(b) Fouled anolyte.

BPT 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 44.840 20.000

Arsenic 32.650 14.530

Mercury 3.906 1.562

Total suspended solids 640.600 304.700

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.

(c) Cathode Antimony Wash Water.

BPT 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 89.680 40.000

Arsenic 65.310 29.060

Mercury 7.812 3.125

Total suspended solids 1,281.000 609.300

pH (1) (1)

1 Within the range of 7.5 to 10.0 at all times.