The article appears in the publication’s October 15, 2025, edition. Their coauthors were Matthew Lahvis and Wayne Jones of Shell Oil Products.
Robbie is a Senior Principal Environmental Scientist based in California with more than 35 years of experience focused on soil vapor extraction system design, vapor emission estimation, and migration of subsurface-contaminant vapor to indoor air. He was a coauthor of the Johnson and Ettinger model and has published numerous influential articles related to vapor intrusion.
Rafat is a Senior Consultant based in California with more than 35 years of experience focused on vapor intrusion and on remediation of manufacturing, commercial, agricultural, dry-cleaning, and military sites. As Chief of Site Mitigation and Brownfield Program at the California Environmental Protection Agency DTSC, he helped develop the RCRA Corrective Action program and more than two dozen vapor intrusion guidance documents.
Groundwater Monitoring & Remediation publishes papers addressing treatment technologies and pairs innovative research with practical solutions. The journal is published by the National Ground Water Association (NGWA), which advances groundwater knowledge while supporting, connecting, and advocating for members.
More Information on Choosing and Using Attenuation Factors for Vapor Intrusion
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To learn more about vapor intrusion assessment and mitigation, contact Robbie at REttinger@Geosyntec.com or Rafat at
Rafat.Abbasi@Geosyntec.com.
Learn more about Robbie: Robert Ettinger
Learn more about Rafat: Rafat Abbasi
