EPA approves the State implementation plan (SIP) revisions submitted by the State of North Dakota with letters dated June 26, 1990, June 30, 1992, and April 29, 1994. The revisions address air pollution control rules regarding general provisions; emissions of particulate matter and organic compounds; new source performance standards (NSPS); national emission standards for hazardous air pollutants (NESHAPs); construction and operating permit programs; prevention of significant deterioration (PSD) of air quality; and control of emissions from oil and gas well production facilities. The April 29, 1994 submittal also addressed the following two issues which will be acted on in separate documents: Revisions to the PSD rules with respect to PM<INF>10 increments; and revisions to the visibility monitoring chapter of the SIP. Further, EPA is approving the State's construction permit and federally enforceable State operating permit (FESOP) programs under section 112(l) of the amended Clean Air Act (Act) for the purposes of creating federally enforceable permit conditions for sources of hazardous air pollutants (HAPs).