The provisions of this subpart are applicable to discharges resulting from the smelting of ferroalloys in covered electric furnaces or other smelting operations, not elsewhere included in this part, with wet air pollution control devices. This subcategory includes those electric furnaces of such construction or configuration (known as covered, closed, sealed, semi-covered or semi-closed furnaces) that the furnace off-gases are not burned prior to collection and cleaning, and which off-gases are cleaned after collection in a wet air pollution control device such as a scrubber, ‘wet’ baghouse, etc. This subcategory also includes those non- electric furnace smelting operations, such as exothermic (i.e., aluminothermic or silicothermic) smelting, ferromanganese refining, etc., where these are controlled for air pollution by wet air pollution control devices. This subcategory does not include noncontact cooling water or those furnaces which utilize dry dust collection techniques, such as dry baghouses.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in part 401 of this chapter shall apply to this subpart.

(b) The term Mwh shall mean megawatt hour(s) of electrical energy consumed in the smelting process (furnace power consumption).

Except as provided in §§ 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 (BPT):

The following limitations establish the quantity or quality of pollutants or pollutant properties, controlled by this section, which may be discharged by a point source subject to the provisions of this subpart after application of the best available technology economically achievable:

The following standards of performance establish the quantity or quality of pollutants or pollutant properties, controlled by this section, which may be discharged by a new source subject to the provisions of this subpart:

Any new source subject to this subpart that introduces process wastewater pollutants into a publicly owned treatment works must comply with 40 CFR part 403.

Except as provided in §§ 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 conventional pollutant control technology (BCT): The limitations shall be the same as those specified for conventional pollutants (which are defined in § 401.16) in § 424.22 of this subpart for the best practicable control technology currently available (BPT).