Matthew A. Lahvis
Global R&D Team Lead - Soil and Groundwater
Shell Global Solutions
Matt holds a Bachelor’s Degree in Geology from Bucknell University, a Master’s Degree in Engineering Geology from Drexel University, and a Ph. D. in Civil Engineering from Drexel University. His research focused on quantifying fate and transport of petroleum compounds in the unsaturated zone at gasoline-spill sites. Matt joined the New Jersey District office of the U.S. Geological Survey in 1989 and served as an adjunct professor in the Civil Engineering Department at Drexel University from 1995-1999. In 2000, Matt joined Shell Projects and Technology where he serves as Function Lead for the Soil and Groundwater R&D Program. Matt has published extensively on vapor transport in the unsaturated zone and has been serving as an Associate Editor for the Ground Water Monitoring and Remediation Journal since 2005.
PLATFORM PRESENTER – Vapor Intrusion: Don't Hold Your Breath
Update on Vertical Screening Distances for Assessing Petroleum Vapor Intrusion Risks at Underground Storage Tank Sites
Vertical screening distances are not recommended for application at petroleum underground storage tank (UST) sites with historic releases of leaded gasoline because of a lack of empirical data on the fuel additives 1,2 dichloroethane (1,2 DCA) and ethylene dibromide (EDB). These compounds are a concern for petroleum vapor intrusion (PVI) because of their relative toxicity (i.e., low soil-gas RBSLs), volatility, and persistence in groundwater. Vertical screening distances have also not been rigorously evaluated for petroleum mixtures, such as Total Petroleum Hydrocarbon (TPH), C5-C8 Aliphatics, C9–C12 Aliphatics, and C9–C10 Aromatics, nor the common TPH fraction surrogates, n-hexane and naphthalene. These compounds are a PVI concern in some regulatory jurisdictions. This study will summarize the derivation of vertical screening distances for the lead scavengers, TPH mixtures, and surrogate compounds based on analyses of paired (co-located/concurrent) soil-gas/groundwater data collected at numerous UST release sites located in US, Canada, and Australia.