Approval and Promulgation of Air Quality Implementation Plans; Delaware; Amendments to the Regulatory Definition of Volatile Organic Compounds

The Environmental Protection Agency (EPA) is approving a state implementation plan (SIP) revision submitted by the State of Delaware. The revisions pertain to amendments made to the definition of volatile organic compound (VOC) in the Delaware Administrative Code to conform with EPA's regulatory definition of VOC. EPA found that certain compounds have negligible photochemical reactivity and, therefore, has exempted them from the regulatory definition of VOC in several rulemaking actions. This revision to the Delaware SIP requested the exemption of eight compounds from the regulatory definition of VOC to match the actions EPA has taken. The revision also requested to remove the recordkeeping, reporting, modeling, and inventory requirements for t-butyl acetate (TBAC). EPA is approving these revisions to update the definition of VOC in the Delaware SIP in accordance with the requirements of the Clean Air Act (CAA).