EPA is approving a State Implementation Plan (SIP) revision submitted by the State of Maryland. This SIP revision amends the requirements for major new sources and major modifications to existing sources of volatile organic compounds (VOCs), and nitrogen oxides (NO<INF>X</INF>) to meet certain new source review (NSR) permitting requirements if they are proposing to locate or are located within the State of Maryland. These NSR requirements apply not only in those portions of Maryland designated as ozone nonattainment areas, but throughout the State of Maryland as the entire state is located within the Ozone Transport Region (OTR). EPA is fully approving Maryland's NSR program in the Maryland portion of the Metropolitan Washington, DC Ozone Nonattainment Area and throughout the State of Maryland with the exception of the Baltimore Ozone Nonattainment Area and the Maryland portion (Cecil County) of the Philadelphia- Wilmington-Trenton Ozone Nonattainment Area. In the Baltimore Ozone Nonattainment Area and in Cecil County, EPA is granting limited approval of Maryland's NSR regulations because they are more stringent than the currently approved NSR program and serve, therefore, to strengthen the SIP. The intended effect of this action is to grant approval of Maryland's NSR regulations.