July 17, 2018

Helen Dawson and Todd McAlary Co-authored Update of the U.S. Department of Defense Tri-Services Vapor Intrusion Handbook

(L-R) Helen Dawson, Todd McAlary (L-R) Helen Dawson, Todd McAlary

Helen Dawson, Ph.D. (Washington D.C.), and Todd McAlary, Ph.D., P.Eng., P.G. (Toronto) co-authored six vapor intrusion (VI) technology fact sheets recently published by the U.S. Department of Defense (DoD).

The VI fact sheets were developed by the DoD Tri-Services Environmental Risk Assessment Workgroup (TSERAWG) for the purpose of updating and supplementing the DoD Vapor Intrusion Handbook published by the TSERAWG in 2009. State-of-the-art VI assessment approaches and technologies described in the fact sheets include use of passive sampling, real time monitoring, high volume soil gas sampling, use of building pressure cycling, use of tracers, surrogates, and indicator parameters, and determining the influence of background sources on indoor air. This collection of facts sheets effectively expands the number of VI investigation tools available to DoD environmental professionals and provides a framework for improving data quality in VI assessments.

Helen is a Principal Civil and Environmental Engineer based in Washington, D.C. with more than 30 years of experience focused on private practice, academia, and public service. Her practice spans a wide range of technical disciplines including vapor intrusion, groundwater characterization, and contaminant fate and transport modeling related to the spread of dense non-aqueous phase liquids, chlorinated solvents, and metals in the environment.

Todd is a Senior Principal Engineer with more than 30 years of international consulting experience focused on the evaluation of contaminant fate and transport in soil and groundwater.

DoD primarily conducts environmental restoration activities in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also known as Superfund. The Department began cleaning up contamination in 1975 under the Installation Restoration Program (IRP). The IRP addresses contamination from a hazardous substance or pollutant or contaminant. In 2001, DoD established the Military Munitions Response Program (MMRP) to address sites (referred to munitions response sites or MRSs) known or suspected to contain unexploded ordnance, discarded military munitions, or munitions constituents. Through the IRP and MMRP, DoD complies with environmental cleanup laws, such as CERCLA.

Under the Defense Environmental Restoration Program (DERP), DoD conducts cleanup at active installations, Formerly Used Defense Sites (FUDS), and Base Realignment and Closure (BRAC) locations. The Army, Navy, Air Force, and Defense Logistics Agency manage the cleanup programs at their active installations and BRAC locations. The Army oversees the U.S. Army Corps of Engineers' execution of the FUDS cleanup program. The Office of the Secretary of Defense, through the Deputy Under Secretary of Defense for Installations and Environment, Environment, Safety, and Occupational Health Directorate, manages and oversees the DERP and provides program guidance.

More Information

The Defense Environmental Restoration Program published the fact sheets on-line and they can be downloaded for free here: https://www.denix.osd.mil/irp/vaporintrusion/.
For consultation regarding vapor intrusion, contact Helen Dawson at This email address is being protected from spambots. You need JavaScript enabled to view it.
 or Todd McAlary at This email address is being protected from spambots. You need JavaScript enabled to view it..
Learn more about Helen at: https://www.geosyntec.com/people/helen-dawson
Learn more about Todd at: https://www.geosyntec.com/people/todd-mcalary

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