Approval and Promulgation of State Implementation Plans and Redesignation of Areas for Air Quality; Planning Purposes: States of Washington and Oregon

The Environmental Protection Agency (EPA) is redesignating the Portland/Vancouver (Pdx/Van) interstate nonattainment area to attainment for the ozone (O<INF>3</INF>) air quality standard and approving a Maintenance Plan that will insure that the area remains in attainment. Under the Clean Air Act, as amended in 1990 (the CAA), designations can be revised if sufficient data are available to warrant such revisions and the request to redesignate shows that all of the requirements of section 107(d)(E)(3) of the CAA have been met. EPA is approving the Washington and Oregon Maintenance Plans and other redesignation submittals because they meet the Maintenance Plan and redesignation requirements, and will ensure that the area remains in attainment. The approved Maintenance Plans will become a federally enforceable part of the Oregon and Washington State Implementation Plans (SIPs). In this action, EPA is also approving the Washington and Oregon 1990 baseline emission inventories for this area, revisions to the approved Inspection and Maintenance (I/M) SIPs of both States, and a number of other O<INF>3</INF> supporting revisions to both SIPs.