40 CFR 420.42: Effluent limitations representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available (BPT).

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.

(a) Electric arc furnace steelmaking—semi-wet. No discharge of process wastewater pollutants to navigable waters.

(b) Basic oxygen furnace steelmaking—wet-suppressed combustion.

Subpart D

Pollutant or pullutant property BPT effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days

Kg/kkg (pounds per 1,000 lb) of Product

TSS 0.0312 0.0104

pH (1) (1)

1 Within the range of 6.0 to 9.0

(c) Basic oxygen furnace steelmaking—wet open combustion; and electric arc furnace steelmaking—wet.

Subpart D

Pollutant or pollutant property BPT effluent limitations

Maximum for any 1 day Average of daily values for 30 consecutive days

Kg/kkg (pounds per 1,000 lb) of product

TSS 0.0687 0.0229

pH (1) (1)

1 Within the range of 6.0 to 9.0.

(d) Basic oxygen furnace steelmaking—semi-wet. (1) No discharge of process wastewater pollutants to navigable waters.

(2) If the permittee demonstrates to the satisfaction of the permitting authority that safety considerations prevent attainment of these limitations, the permitting authority may establish alternative limitations on a best professional judgment basis.