Search

This report includes findings and results from the demonstration of passive samplers and building pressure control in eight Department of Defense (DoD) sites. Due to the nature of the methods, as well as to programmatic factors, researchers were unable to demonstrate both methods at all of the sites, and some of the sites were only tested with one of the two methods. However, the experience and recommendations developed from these demonstrations is applicable to many other DoD and industrial sites in general. Navy site managers and the public can use this technical report to apply passive samplers and/or build pressure control supporting improved VI assessment by following methodology proved in this effort, which is available to the regulatory and scientific communities, as well as to the general user. The recommendations specifically provide direction on the collection of indoor air and soil gas samples supporting vapor intrusion assessment. This top-down approach should provide the appropriate information required to support No Further Action at sites eligible for such action. The potential for return on investment for this project is significant because it can provide a basis for continued research and provide cost-effective, accepted solutions to support effective vapor intrusion assessment. The results from these demonstrations attest to the capability of passive samplers and building pressure control for assessment of vapor intrusion. These demonstrations provided information of the use of passive samplers for long-term quantification of VOCs. They also provided the knowledge for correct use of passive samplers under a suite of conditions. Similarly, it was demonstrated that building pressure control could assess indoor sources, VI, and the worst-case scenario for positive vapor intrusion., Prepared in cooperation with Geosyntec Consultants, Inc., Atlanta, GA, and GSI Environmental, Inc, Houston, TX.

Vapor intrusion (VI) refers to the movement of chemical vapors from contaminated soils or groundwater through the subsurface and into buildings (indoor air). This exposure pathway has attracted significant attention from regulatory agencies over the past decade in response to several well-publicized cases. Virtually all of the current regulatory documents generated are guidance and have not been promulgated as law, allowing for negotiation on the approach to follow in accordance to site-specific conditions. Nevertheless, experience indicates that this guidance also leads to higher costs in mitigation, public relations, and potential litigation. In response to the need for future research and development on reducing high costs and uncertainties of VI assessment strategies (Department of the Navy, DON, 2008), the objective of this report is to identify existing best practices, knowledge and data gaps, and future research into new strategies and techniques. This study was supported by the Navy Environmental Sustainability Development to Integration Program (NESDI) Program, as part of the study on Improved Strategies for Assessment of Vapor Intrusion, under direction by the Space and Naval Warfare (SPAWAR) Systems Center Pacific., Prepared in collaboration with Geosyntec Consultants, Inc., Arizona Sate University, URS Corp., and Air Toxics Limited.