Advisory - Active Soil Gas Investigations (January 2003) Developed by the DTSC and Los Angeles Regional Water Quality Control Board (LARWQCB), this Advisory provides technically consistent approaches for collecting and analyzing soil gas samples. The 2003 Cal/EPA "Advisory - Active Soil Gas Investigation" and 1997 LARWQCB "Interim Guidance for Active Soil Gas Investigation" were addressed at the Soil Gas Advisory Forum in March 2008. The public comment period for the revised version of Cal/EPA's Advisory - Active Soil Gas Investigations (March 2010) closed on April 15, 2010. The document is now in the process of being finalized with consideration of the comments received. The Advisory is expected to be issued in early 2012.
New!Final Guidance for the Evaluation & Mitigation of Subsurface Vapor Intrusion to Indoor Air (October 2011; also known as the Vapor Intrusion Guidance) DTSC's Vapor Intrusion Guidance provides a stepwise and sometimes iterative process for the investigation of vapor intrusion and describes procedures for screening and site-specific evaluation of potential risks associated with this exposure pathway. Indoor air concentrations estimated from soil gas or groundwater concentrations by fate and transport models for vapor intrusion and/or measured indoor air concentrations are used in the assessment. Models for estimating indoor air concentrations include default attenuation factors for vapor migration from soil gas or groundwater to indoor air, and default and site-specific inputs to the U.S. EPA version of the Johnson and Ettinger vapor intrusion model.
New!Vapor Intrusion Mitigation Advisory, Revision 1 (October 2011) Provides a framework that guides the reader through the decision process for 1) determining if mitigation is appropriate for the project site, 2) selecting a mitigation system that is protective of human health, and 3) ensuring that implementation is sustainable for the duration of mitigation. Emphasizes public participation and implementation considerations. Identifies likely technologies for vapor intrusion mitigation, but does not identify proven technologies.
Vapor Intrusion Public Participation Advisory (Expected 2012) DTSC developed this Advisory to help determine and implement appropriate public participation coordination and activities at sites where a potential vapor intrusion risk has been identified. The Advisory is a companion document to DTSC's Vapor Intrusion Guidance and Vapor Intrusion Mitigation Advisory. In addition, the Advisory supplements DTSC's Public Participation and Procedures Manual.
PT&R Guidance - Remediation of Chlorinated VOCs in Vadose Zone Soil (DTSC 2010) Presents an option for expediting and encouraging cleanup of sites with chlorinated volatile organic compounds (VOCs) in vadose zone soil. Applicable on a case-by-case basis to operating and closing hazardous waste facilities and Brownfields sites. Streamlines the cleanup process by: limiting the site-specific remedy evaluation to excavation/disposal and soil vapor extraction (SVE); providing guidance for selecting screening levels and cleanup goals; and providing resources that facilitate remedy implementation, documentation, and administrative processes.
ITRC periodically hosts a 2-day ITRC classroom training on Vapor Intrusion. This training provides strategies to conduct site screening and investigations; determine what tools are appropriate to collect quality data and evaluate the results; apply multiple lines of evidence to ensure quality decision-making; build solutions for vapor intrusion issues through understanding of mitigation options; and network with environmental professionals dealing with this interdisciplinary and complex pathway. For more information please visit the ITRC website.
