The Environmental Protection Agency (EPA) is approving a State Implementation Plan (SIP) revision submitted by the State of Montana on May 24, 2018. The revisions remove a prohibition on the open burning of asbestos and asbestos-containing materials located in the SIP-approved Administrative Rules of Montana (ARM) Title 17, chapter 8, subchapter 6 and the similar provision in the SIP-approved Lincoln County Air Pollution Control Program. The revisions also remove a corresponding cross-reference located in SIP-approved ARM Title 17, chapter 8, subchapter 3 (concerning wood-waste burners). The EPA is taking this action pursuant to the Clean Air Act (CAA).