A Quantitative Relative Ranking Approach to Prioritize Multiple Sites for Vapor Intrusion Potential Using Best Practices and Multiple Lines of Evidence(ABSTRACT)

摘要

The focus on vapor intrusion (VI) into occupied buildings continues to increase nationally and within the regulatory community. Vapor intrusion investigations and mitigation activities have been occurring at various sites since the 1990s. The knowledge and experience about VI has increased considerably in the last decade. Consistent with USEPA's (2010) “Review of the 2002 Draft Guidance,” this has led to an improved understanding of the factors and methods that affect VI assessment and management. The Office of the Inspector General requested in 2009 that USEPA incorporate state-of-the-practice knowledge into a revised VI guidance by 2012. USEPA (2011) also recently indicated that VI is being considered for determining if a site should be included on the National Priorities List (NPL). Methods for quantitatively ranking and prioritizing sites will need to be considered prior to USEPA making this decision. A quantitative relative ranking and prioritization process was conducted for approximately 30 volatile organic compound (VOC) impacted sites in order to: (1) insure that current best practices are being used to identify and prioritize VI sites; (2) verify that the sites with the highest potential for VI have been or continue to be investigated and/or mitigated; and 3) compare the VI investigation and/or mitigation strategies being used at these sites across the country.