40 CFR 420.47: Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology (BCT).

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

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

(c) Basic oxygen furnace steelmaking—wet—open combustion; electric arc furnace steelmaking—wet. [Reserved]

(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.