Federal Implementation Plan for the Astaris-Idaho LLC Facility (formerly owned by FMC Corporation) in the Fort Hall PM-10 Nonattainment Area

The Environmental Protection Agency (EPA, Agency or we) is taking final action on a Federal Implementation Plan (FIP) to control particulate matter emissions from an elemental phosphorus facility owned by Astaris-Idaho LLC (formerly owned by FMC Corporation) in southeastern Idaho (Astaris facility). The Astaris facility is located on the Fort Hall Indian Reservation and in an area known as the Fort Hall PM-10 nonattainment area. The Fort Hall PM-10 nonattainment area is not in attainment with the national ambient air quality standards (NAAQS) for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (PM-10). The purpose of the FIP is to impose emission limits and work practice requirements that constitute reasonably available control technology (RACT) for particulate matter and that will, in light of this area's longstanding nonattainment problem, ensure expeditious progress towards improving air quality and attaining the PM-10 standards in order to protect the public health.