Please join Wayne State University's Center for Leadership in Environmental Awareness and Research (CLEAR) and Center for Urban Responses to Environmental Stressors (CURES) for their upcoming seminar on November 13, 2025 from 12:30 to 1:30 p.m. The seminar is free; registration is required. The meeting will be held in person and via Zoom. The Zoom link will be emailed to all registrants prior to the seminar.

The speaker will be Bryan VanDuinen from Geosyntec Consultants who will present, "Vapor intrusion: Challenges, solutions, attenuation factors." 

Abstract

Vapor intrusion (VI) is a process where chemicals in soil and groundwater volatilize, migrate as vapors through soil, and enter the indoor air of overlying buildings. Typically, the extent of contaminants in soil and groundwater that can act as a vapor source is determined, and buildings within a “lateral inclusion zone” of that vapor source are assessed. A building’s susceptibility to VI can be characterized by an attenuation factor, which is the ratio of chemical concentrations in the indoor air and subsurface. Attenuation factors are used to calculate generic and site-specific screening levels.

Evaluating VI is often challenging because of the potential for background sources, spatial and temporal variability, and preferential pathways. Conventional sampling methods may not provide clear-cut answers. Innovative tools can be used to evaluate VI quickly and cost-effectively. High volume sampling (HVS) can be used to identify source areas, manage spatial variability in soil gas, and understand how vapor flows underneath and into a building. Building pressure control (BPC) can be used to manage temporal variability in indoor air and identify background sources. Case studies describing how these tools were applied to investigate VI sites in Michigan will be presented.

Biography

Bryan VanDuinen, PE (MI) is a professional environmental engineer with 13 years of experience in assessing and remediating sites, particularly those impacted by chlorinated solvents or with vapor intrusion (VI) risks. Bryan has implemented innovative VI assessment techniques, including building pressure control (BPC), high volume sampling, and passive soil gas sampling, at multiple sites in Michigan for rapid characterization of VI risks and for design of VI mitigation and soil vapor extraction systems. Bryan also helped to develop and validate standard operating procedures for BPC and other VI sampling methodologies for the Michigan Department of Environment, Great Lakes, and Energy (EGLE). He is the VI point of contact for Geosyntec’s Michigan offices.

We hope you are able to join us for this interesting presentation.