Environmental Protection Agency April 19, 2011 – Federal Register Recent Federal Regulation Documents

EPA is proposing to approve portions of a State Implementation Plan (SIP) revision submitted by the State of Colorado for the purpose of addressing the ``good neighbor'' provisions of Clean Air Act (``Act'' or ``CAA'') section 110(a)(2)(D)(i) for the 1997 8-hour ozone National Ambient Air Quality Standards (``NAAQS'' or ``standards'') and the 1997 fine particulate matter (``PM2.5'') NAAQS. This SIP revision addresses the requirement that the State of Colorado's SIP (``Interstate Transport SIP'') have adequate provisions to prohibit air emissions from adversely affecting another state's air quality through interstate transport. In this action, EPA is proposing to approve the Colorado Interstate Transport SIP provisions that address the requirement of section 110(a)(2)(D)(i) that emissions from Colorado sources do not significantly contribute to nonattainment of the 1997 PM2.5 NAAQS in any other state, interfere with maintenance of the 1997 PM2.5 NAAQS by any other state, or interfere with any other state's required measures to prevent significant deterioration of air quality for the 1997 PM2.5 and 8-hour ozone NAAQS. This action is being taken under section 110 of the CAA.

EPA is finalizing two determinations regarding attainment for the Truckee Meadows PM-10 nonattainment area in Washoe County, Nevada (``Truckee Meadows area''). First, EPA is finalizing its determination that, based on complete and quality-assured air monitoring data for 1999-2001, the Truckee Meadows area did not attain the 24-hour National Ambient Air Quality Standard (``NAAQS'') for particulate matter with an aerodynamic diameter less than or equal to a nominal 10 micrometers (``PM-10'') by the applicable attainment date of December 31, 2001. Second, EPA is finalizing its determination that the Truckee Meadows area is currently attaining the PM-10 NAAQS, based upon complete, quality-assured PM-10 air quality monitoring data during the years 2007-2009. Preliminary data through June 2010 contained in EPA's Air Quality System (``AQS'') are also consistent with continued attainment of the 24-hour PM-10 NAAQS. Because the Truckee Meadows area is currently attaining the PM-10 NAAQS, EPA is also finalizing its determination that the obligation to make submissions to meet certain Clean Air Act (``CAA'' or ``the Act'') requirements related to attainment is not applicable for as long as the area continues to attain the PM-10 NAAQS.