Title 40 · EPA

Ferroalloy Manufacturing Point Source Category

40 C.F.R. Part 424 · Updated July 1, 2025

§ 424.10 — Applicability; description of the open electric furnaces with wet air pollution control devices subcategory.

The provisions of this subpart are applicable to discharges resulting from the smelting of ferroalloys in open electric furnaces with wet air pollution control devices. This subcategory includes those electric furnaces of such construction or configuration that the furnace off-gases are burned above the furnace charge level by air drawn into the system. After combustion the gases are cleaned in a wet air pollution control device, such as a scrubber, an electrostatic precipitator with water or other aqueous sprays, etc. The provisions of this subpart are not applicable to noncontact cooling water or to those electric furnaces which are covered, closed, sealed, or semi-covered and in which the furnace off-gases are not burned prior to collection (regulated in subpart B of this part).

§ 424.11 — Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 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).

§ 424.12 — 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 §§ 125.30 through 125.32, and subject to the provisions of paragraph (a) of this section, 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):

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

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:

§ 424.14 — [Reserved]

§ 424.15 — Standards of performance for new sources.

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:

§ 424.16 — Pretreatment standards for new sources.

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.

§ 424.17 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

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 § 424.12 of this subpart for the best practicable control technology currently available (BPT).

§ 424.20 — Applicability; description of the covered electric furnaces and other smelting operations with wet air pollution control devices subcategory.

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.

§ 424.21 — Specialized definitions.

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).

§ 424.22 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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

§ 424.24 — [Reserved]

§ 424.25 — Standards of performance for new sources.

§ 424.26 — Pretreatment standards for new sources.

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.

§ 424.27 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

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).

§ 424.30 — Applicability; description of the slag processing subcategory.

The provisions of this subpart are applicable to discharges resulting from slag processing, wherein: (a) The residual metallic values in the furnace slag are recovered via concentration for return to the furnace, or (b) the slag is “shotted” for other further use.

§ 424.31 — Specialized definitions.

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.

§ 424.32 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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

§ 424.34 — [Reserved]

§ 424.35 — Standards of performance for new sources.

§ 424.36 — Pretreatment standards for new sources.

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.

§ 424.37 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

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 § 424.32 of this subpart for the best practicable control technology currently available (BPT).

§ 424.40 — Applicability; description of the covered calcium carbide furnaces with wet air pollution control devices subcategory.

The provisions of this subpart are applicable to discharges resulting from the production of calcium carbide in covered electric furnaces which use 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 does not include noncontact cooling water or those furnaces which utilize dry dust collection techniques, such as dry baghouses.

§ 424.41 — Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

§ 424.42 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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

§ 424.44-424.46 — 424.44-424.46 [Reserved]

§ 424.47 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

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 § 424.42 of this subpart for the best practicable control technology currently available (BPT).

§ 424.50 — Applicability; description of the other calcium carbide furnaces subcategory.

The provisions of this subpart are applicable to discharges resulting from the production of calcium carbide in those covered furnaces which do not utilize wet air pollution control methods. Covered calcium carbide furnaces using wet air pollution control devices are regulated in subpart D of this part. Open (uncovered) calcium carbide furnaces are regulated in part 415, inorganic chemicals manufacturing point source category (39 FR 9612).

§ 424.51 — Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

§ 424.52 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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

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 the best available technology economically achievable: There shall be no discharge of process waste water pollutants to navigable waters.

§ 424.54-424.56 — 424.54-424.56 [Reserved]

§ 424.57 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

The following limitations establish the quantity or quality of pollutants or pollutant properties, which may be discharged by a point source subject to the provisions of this subpart after application of the best conventional pollutant control technology: There shall be no discharge of process waste water pollutants to navigable waters.

§ 424.60 — Applicability; description of the electrolytic manganese products subcategory.

The provisions of this subpart are applicable to discharges resulting from the manufacture of electrolytic manganese products such as electrolytic manganese metal or electrolytic manganese dioxide.

§ 424.61 — Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

(b) [Reserved]

§ 424.62 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

(a) 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 producing electrolytic manganese after application of the best practicable control technology currently available:

(b) 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 producing electrolytic manganese dioxide after application of the best practicable control technology currently available:

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

(a) 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 producing electrolytic manganese after application of the best available technology economically achievable:

§ 424.64-424.66 — 424.64-424.66 [Reserved]

§ 424.67 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

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 § 424.62 of this subpart for the best practicable control technology currently available (BPT).

§ 424.70 — Applicability; description of the electrolytic chromium subcategory.

The provisions of this subpart are applicable to discharges resulting from the manufacture of chromium metal by the electrolytic process. They are not applicable to discharges resulting from the manufacture of chromium metal by aluminothermic or other methods.

§ 424.71 — Specialized definitions.

For the purpose of this subpart:

(a) Except as provided below, the general definitions, abbreviations and methods of analysis set forth in 40 CFR part 401 shall apply to this subpart.

§ 424.72 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best practicable control technology currently available.

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

§ 424.74-424.76 — 424.74-424.76 [Reserved]

§ 424.77 — Effluent limitations guidelines representing the degree of effluent reduction attainable by the application of the best conventional pollutant control technology.

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 § 424.72 of this subpart for the best practicable control technology currently available (BPT).