Air Quality State Implementation Plans; Approval and Promulgations; Hawaii; Infrastructure SIP

The Environmental Protection Agency (EPA) is approving a state implementation plan (SIP) submission from the State of Hawaii regarding certain Clean Air Act (CAA or "Act") requirements related to interstate transport for the 2008 ozone national ambient air quality standards (NAAQS). The interstate transport requirements consist of several elements; this approval pertains only to provisions requiring that SIPs prohibit sources or other types of emissions activity in one state from emitting any air pollutant in amounts that will contribute significantly to nonattainment and interference with maintenance of the 2008 ozone NAAQS in other states. The EPA is approving Hawaii's August 6, 2015 SIP submittal on the basis that it addresses two requirements of CAA section 110(a)(2)(D)(i)(I), which we refer to as prong 1 (significant contribution to nonattainment of the NAAQS in any other state) and prong 2 (interference with maintenance of the NAAQS in any other state). The EPA refers to SIP revisions addressing the requirements of section 110(a)(2)(D)(i)(I) as "good neighbor SIPs" or "interstate transport SIPs."