The Environmental Protection Agency (EPA) is making an interim final determination that the California Air Resources Board (CARB) has submitted a Clean Air Act (CAA or "Act") State implementation plan (SIP) revision on behalf of the Placer County Air Pollution Control District (PCAPCD or "District") that corrects deficiencies concerning the District's nonattainment new source review stationary source permitting program. This determination is based on a proposed approval, published elsewhere in this issue of the Federal Register, of PCAPCD Rule 502, "New Source Review." The effect of this interim final determination is to defer sanctions that were triggered by the EPA's previous limited disapproval of PCAPCD Rule 502 in 2023.