(a) As defined more specifically in subpart A, except as provided in paragraphs (b) through (e) of this section, this part applies to process wastewater discharges from oily operations (as defined at § 438.2(f) and appendix B of this part) to surface waters from existing or new industrial facilities (including facilities owned and operated by Federal, State, or local governments) engaged in manufacturing, rebuilding, or maintenance of metal parts, products, or machines for use in the Metal Product & Machinery (MP&M) industrial sectors listed in this section. The MP&M industrial sectors consist of the following:

(b) The regulations in this part do not apply to process wastewaters from metal-bearing operations (as defined at § 438.2(d) and appendix C of this part) or process wastewaters which are subject to the limitations and standards of other effluent limitations guidelines (e.g., Metal Finishing (40 CFR part 433) or Iron and Steel Manufacturing (40 CFR part 420)). The regulations in this part also do not apply to process wastewaters from oily operations (as defined at § 438.2(f) and appendix B of this part) commingled with process wastewaters already covered by other effluent limitations guidelines or with process wastewaters from metal-bearing operations. This provision must be examined for each point source discharge at a given facility.

(c) Wastewater discharges resulting from the washing of cars, aircraft or other vehicles, when performed only for aesthetic or cosmetic purposes, are not subject to this part. Direct discharges resulting from the washing of cars, aircraft or other vehicles, when performed as a preparatory step prior to one or more successive manufacturing, rebuilding, or maintenance operations, are subject to this part.

(d) Wastewater discharges from railroad line maintenance facilities (as defined at § 438.2(h)) are not subject to this part. Wastewater discharges from railroad overhaul or heavy maintenance facilities (as defined at § 438.2(i)) may be covered by subpart A of this part, the Metal Finishing Point Source Category (40 CFR part 433), or by other effluent limitations guidelines, as applicable.

(e) The following wastewater discharges are not subject to this part:

(1) Non-process wastewater as defined at § 438.2(e).

(2) Wastewater discharges introduced into a Publicly Owned Treatment Works (POTW) or a Federally owned and operated Treatment Works Treating Domestic Sewage (TWTDS), as defined at 40 CFR 122.2.

(3) Process wastewater generated by maintenance and repair activities at gasoline service stations, passenger car rental facilities, or utility trailer and recreational vehicle rental facilities.

(4) Wastewater discharges generated from gravure cylinder preparation or metallic platemaking conducted within or for printing and publishing facilities.

(5) Wastewater discharges in or on dry docks and similar structures, such as graving docks, building ways, marine railways, lift barges at shipbuilding facilities (or shipyards), and ships that are afloat.

(6) Wastewater generated by facilities primarily performing drum reconditioning and cleaning to prepare metal drums for resale, reuse, or disposal.