Public Notice Relative Risk Site Evaluation Tulsa Air National Guard Base, Oklahoma The Air Force completed the Relative Risk Site Evaluation (RRSE) for the Tulsa Air National Guard Base (ANGB), Oklahoma, to support sequencing of environmental restoration work. When the term "Air Force" is used in this public notice, it includes the Air National Guard. The RRSE process is used to evaluate the relative risk posed by an environmental restoration site in relation to other sites. Restoration sites in Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) are evaluated during the RRSE process to sequence sites for Remedial Investigation. Due to discovery of per- and polyfluoroalkyl substances (PFAS), which includes perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perfluorobutane sulfonic acid (PFBS), a RRSE was completed for the sites at this installation. Relative risk is not the sole factor in determining the sequence of environmental restoration work, but it is an important consideration in the priority setting process. This RRSE fact sheet with individual site summaries is issued in accordance with the Department of Defense (DoD) Environmental Restoration Program (ERP) and is available for public review for 30 days as of this notice. The public comment period for Tulsa ANGB will be from November 1 - December 1, 2021. At Tulsa ANGB, six restoration sites were evaluated in the current RRSE. The Overall Site Category scores were six "High" and zero "Medium" or "Low" categories. Additional information on the RRSE framework and the scoring process for the sites is included in the RRSE which can be found at the Tulsa ANGB website located at the following link: https://www.138fw.ang.af.mil/. For more information or to submit written comments, please contact Matt Voorhees at 3501 Fetchet Avenue, Joint Base Andrews, MD, 20762-5157, (240) 612-7275.