The Environmental Protection Agency (EPA) is proposing action on two permitting rules submitted as a revision to the Placer County Air Pollution Control District (PCAPCD or ``District'') portion of the California State Implementation Plan (SIP). We are proposing an approval of one rule and proposing a limited approval and limited disapproval of the second rule. These revisions concern the District's New Source Review (NSR) permitting program for new and modified sources of air pollution under title I of the Clean Air Act (CAA). This action updates the District's applicable SIP with revised rules that the District has amended to address deficiencies identified in a previous limited approval and limited disapproval action, as well as other updates related to NSR requirements. We are taking comments on this proposal and plan to follow with a final action.