(a)(1) The requirements of subpart G of this chapter are not met since the control strategy does not analyze the impact of smelter fugitive emissions on ambient air quality (except at Hayden, Arizona) in the Central Arizona Intrastate, the Pima Intrastate, and the Southeast Arizona Intrastate (Cochise and Greenlee counties) Regions. Arizona must submit these smelter fugitive emissions control strategies to EPA by August 1, 1984. In addition, the requirements of § 51.281 of this chapter are not met since the plan does not require permanent control of fugitive smelter emissions necessary to attain and maintain the national standards for sulfur oxides. The control strategy for Hayden shows that these controls are required to attain and maintain the national standards, and the fugitive control strategy analyses required above may show that they are required for some or all of the other smelter towns in Arizona. Arizona must submit all fugitive emissions control regulations necessary to attain and maintain the national standards for sulfur oxides to EPA by August 1, 1984. Therefore, the control strategies and regulations for the six smelter areas in the Central Arizona Intrastate, the Pima Intrastate and the Southeast Arizona Intrastate (Cochise and Greenlee counties) Regions are incomplete due to Arizona's failure to address the fugitive emissions problems at copper smelters.

(2) Regulation 7-1-4.1 (copper smelters) of the Arizona Rules and Regulations for Air Pollution Control, as it pertains to existing copper smelters, is disapproved for the Central Arizona Intrastate, Pima Intrastate and Southeast Arizona Intrastate (Cochise and Greenlee counties) Regions.

(b) The requirements of subpart G and § 51.281 of this chapter are not met since the plan does not provide the degree of control necessary to attain and maintain the national standards for sulfur oxides in the Northern Arizona Intrastate Region. Therefore, Regulation 7-1-4.2(C) (fuel burning installations) of the Arizona Rules and Regulations for Air Pollution Control, as it pertains to existing sources, is disapproved in the Northern Arizona Intrastate Region for steam power generating installations having a total rated capacity equal to or greater than 6,500 million B.t.u. per hour.

(c) Replacement regulation for Regulation 7-1-4.2(C) (Fossil fuel-fired steam generators in the Northern Arizona Intrastate Region). (1) This paragraph is applicable to the fossil fuel-fired steam generating equipment designated as Units 1, 2, and 3 at the Navajo Power Plant in the Northern Arizona Intrastate Region (§ 81.270 of this chapter).

(2) No owner or operator of the fossil fuel-fired steam generating equipment to which this paragraph is applicable shall discharge or cause the discharge of sulfur oxides into the atmosphere in excess of the amount prescribed by the following equations:

(3) For the purposes of this paragraph:

(i) E shall not exceed 21,270 lb./hr. (2,680 gm./sec.).

(ii) If the sum of sulfur oxides emissions from Units 1, 2, and 3 would be less than 3,780 lb./hr. (475 gm./sec.) without the use of emission control equipment, the requirements of paragraphs (2), (4)(i) and (5) of this paragraph (c), shall not apply for the period of time that the emissions remain below this level.

(iii) The applicability of paragraph (c)(2)(ii) of this section may be determined through a sulfur balance utilizing the analyzed sulfur content of the fuel being burned and the total rate of fuel consumption in all affected units.

(4)(i) No owner or operator of the fossil fuel-fired steam generating equipment subject to this paragraph shall discharge or cause the discharge of sulfur oxides into the atmosphere from any affected unit in excess of the amount prescribed by the following equations, except as provided in paragraph (3)(ii) of this paragraph (c).

(ii) The owner or operator of the fossil fuel-fired steam generating equipment to which this paragraph is applicable may submit a request to redesignate the allowable emissions specified in paragraph (c)(4)(i) of this section. Such a request shall be submitted no later than December 2, 1974, and shall demonstrate that sulfur oxides emissions on a total plant basis will not exceed those specified in paragraphs (2) and (3)(i) of this paragraph (c). Upon receipt and evaluation of such request, the Administrator shall consider such and if appropriate, redesignate the allowable emissions specified in paragraph (c)(4)(i) of this section.

(5) All sulfur oxides control equipment at the fossil fuel-fired steam generating equipment to which this paragraph is applicable shall be operated at the maximum practicable efficiency at all times, without regard to the allowable sulfur oxides emissions, determined according to paragraph (2) or (3) of this paragraph (c), except as provided in paragraph (3)(ii) of this paragraph (c).

(6) Compliance with this paragraph shall be in accordance with the provisions of § 52.134(a).

(7) The test methods and procedures used to determine compliance with this paragraph shall be those prescribed in § 60.46(c)(2) and (c)(4) of this chapter. The test methods for determining the sulfur content of fuel shall be those specified in § 60.45(c) and (d) of this chapter.

(d)-(e) [Reserved]

(f)(1) Paragraphs B through E of regulation 7-1-4.2 (R9-3-402) (Sulfur Emissions: Fuel Burning Installations) of the Arizona Air Pollution Control Regulations are disapproved because they could allow existing oil fired facilities to use dispersion dependent techniques alone as a means of attaining and maintaining the national ambient air quality standards. The regulation does not assure the attainment and maintenance of the national standards in a manner which is consistent with the intent of sections 110(a)(2)(B) and 123(a)(2) of the Clean Air Act.

(2) The approval of paragraphs A and F of regulation 7-1-4.2 as to coal fired facilities does not apply to the Salt River Project Agricultural Improvement and Power District-Navajo Generating Station.

(3) Paragraphs B through E of regulation 8-1-4.2 (Sulfur Emissions—Fuel Burning Installations) of the Yuma County Air Pollution Control Regulations are disapproved because they could allow existing facilities to use dispersion dependent techniques alone as a means of attaining and maintaining the National Ambient Air Quality Standards. This regulation does not assure the attainment and maintenance of the national standards in a manner which is consistent with the intent of sections 110(a)(2)(B)and 123(a)(2) of the Clean Air Act.

(g) Section 3, Regulation 3 (Sulfur from Primary Copper Smelters) of the Mohave County Health Department Air Pollution Control Regulations and Regulation 7-3-2.1 (Copper Smelters) of the Pinal-Gila Counties Air Quality Control District are disapproved since Section 36-1706 of the Arizona Revised Statutes grants exclusive jurisdiction to the Arizona Department of Health Services and the State Hearing Board over all existing copper smelters.

(1) The requirements of § 51.13 of this chapter are not met since the plan does not demonstrate that the emission limitations applicable to existing fuel burning equipment producing electrical energy will provide for the attainment and maintenance of the national standards in the Pima Intrastate Region (§ 81.269 of this chapter).

(2) Regulation II: Rule 7A—paragraphs 2 through 5, Emission Limitations Fuel Burning Equipment—Sulfur Dioxide, of the Rules and Regulations of the Pima County Air Pollution Control District are disapproved because they could allow existing facilities to use dispersion dependent techniques along as a means of attaining and maintaining the National Ambient Air Quality Standards. The regulation does not assure the attainment and maintenance of the national standards in a manner which is consistent with the intent of section 110(a)(2)(B) of the Clean Air Act.

(h) Effective March 2, 2022, the EPA has determined that the Hayden and Miami nonattainment areas failed to attain the 2010 1-hour primary sulfur dioxide (SO2) national ambient air quality standards (NAAQS) by the applicable attainment date of October 4, 2018. This determination triggers the requirements of CAA section 179(d) for the State of Arizona to submit a revision to the Arizona SIP for the Hayden and Miami nonattainment areas to the EPA by January 31, 2023. The SIP revision must, among other elements, provide for attainment of the 1-hour primary SO2 NAAQS in the Hayden and Miami SO2 NAAs as expeditiously as practicable but no later than January 31, 2027.