§ 57.103 Definitions.

(a) The Act means the Clean Air Act, as amended.

(b) Active use refers to an SO₂ constant control system installed at a smelter before August 7, 1977 and not totally removed from regular service by that date.

(c) Adequate SO₂ emission limitation means a SIP emission limitation which was approved or promulgated by EPA as adequate to attain and maintain the NAAQS in the areas affected by the stack emissions without the use of any unauthorized dispersion technique.

(d) Administrative Law Judge means an administrative law judge appointed under 5 U.S.C. 3105 (see also 5 CFR part 930, as amended by 37 FR 16787), and is synonymous with the term “Hearing Examiner” as formerly used in Title 5 of the U.S. Code.

(e) The Administrator means the Administrator of the U.S. Environmental Protection Agency, or the Administrator's authorized representative.

(f) Ambient air shall have the meaning given by 40 CFR 50.1(e), as that definition appears upon promulgation of this subpart, or as hereafter amended.

(g) Ambient air quality refers only to concentrations of sulfur dioxide in the ambient air, unless otherwise specified.