Approval and Promulgation of Implementation Plans; Washington: Interstate Transport Requirements for the 2008 Lead and 2010 Nitrogen Dioxide National Ambient Air Quality Standards

The Environmental Protection Agency (EPA) is approving a submittal by the Washington Department of Ecology (Ecology) demonstrating that the State Implementation Plan (SIP) meets certain interstate transport requirements of the Clean Air Act (CAA) for the National Ambient Air Quality Standards (NAAQS) promulgated for lead (Pb) on October 15, 2008 and nitrogen dioxide (NO2) on January 22, 2010. Specifically, Ecology conducted an emissions inventory analysis and reviewed monitoring data to show that sources in Washington do not significantly contribute to nonattainment or interfere with maintenance of the 2008 Pb and 2010 NO2 NAAQS in any other state.