The Environmental Protection Agency (EPA) is taking final action to approve the ``Coso Junction PM<INF>10</INF> Planning Area Second 10-Year Maintenance Plan'' (``Coso Junction Second Maintenance Plan'' or ``Plan'') as a revision to the state implementation plan (SIP) for the State of California. The Coso Junction Second Maintenance Plan includes, among other elements, a base year emissions inventory, a maintenance demonstration, and contingency provisions. The EPA is finalizing this action because the SIP revision meets the applicable statutory and regulatory requirements for such plans. The EPA is also taking final action to find the contribution of motor vehicle emissions to the area's continued attainment of the 1987 PM<INF>10</INF> standards to be insignificant. Once this insignificance finding is finalized, the area will not have to complete a regional emissions analysis for any transportation conformity determinations necessary for the Coso Junction Planning Area (CJPA).