U.S. EPA Contaminated Site Cleanup Information (CLU-IN)


U.S. Environmental Protection Agency
U.S. EPA Technology Innovation and Field Services Division

For more information on Vapor Intrusion, please contact:

Michael Adam
Technology Integration and Information Branch

PH: (703) 603-9915 | Email: adam.michael@epa.gov



Vapor Intrusion

Conferences and Training

Conference and Training Archives

March 18, 2014: Vapor Intrusion (VI) Exposures: The Challenges of, Need for, and Benefits of Long Term Stewardship
U.S. Environmental Protection Agency/Association for Environmental Health & Sciences (EPA/AEHS), 18 Mar 2014

This one-day workshop focused on scientific observations and evidence regarding the accessibility and predictability of VI exposures. Presenters provided evidence for the optimal condition and frequency of ongoing monitoring and protection from VI exposure under both natural (varying) and engineered (controlled) attenuation scenarios. The workshop included panel discussions on how the evidence relates to related risk management decision-making and response actions (i.e., balancing criteria) for VI mitigation strategies, as well as case studies of long-term management and refinement of mitigation approaches. Some presentations are posted with both audio and slides and others with slides only.

Adobe PDF LogoDecember 19, 2013: SERDP and ESTCP Workshop on Vapor Intrusion into Indoor Air from Contaminated Groundwater
Unger, M., P. Johnson, A. Leeson, H. Stroo, and C. Lebron.
Strategic Environmental Research and Development Program-Environmental Security Technology Certification Program (SERDP-ESTCP), 16 pp, 2014

SERDP/ESTCP sponsored the vapor intrusion (VI) workshop that was held in Tempe, Arizona, in December 2013 to develop a path forward for DoD investments in VI assessment. This report presents the assessment of needs for VI research and technology transfer.

March 24, 2011 NARPM Presents...Vapor Intrusion Issues at the Hill Air Force Base
(Audio file and PowerPoint slides are archived on the website.)

Two-hour webinar focuses on tools and techniques used to address vapor intrusion issues at the Hill Air Force Base site located in northern Utah.

March 16, 2011 “Petroleum Hydrocarbon Vapor Intrusion”
Workshop held at the Association for Environmental Health and Sciences 21st Annual Meeting and West Coast Conference on Soils, Sediments, and Water - Workshop: Addressing Regulatory Challenges in Vapor Intrusion, San Diego, California

Presentations range from sampling considerations and methods, site conditions conducive to risk, and challenges to multiple lines of evidence evaluations at petroleum release sites.

March 15, 2011 “Addressing Regulatory Challenges in Vapor Intrusion: A State-of-the-Science Update Focusing on Chlorinated VOCs”
Workshop held at the Association for Environmental Health and Sciences 21st Annual Meeting and West Coast Conference on Soils, Sediments, and Water - Workshop: Addressing Regulatory Challenges in Vapor Intrusion, San Diego, California

This technical transfer workshop by the U.S. Environmental Protection Agency’s Offices of Research and Development and Solid Waste and Emergency Response described the state;science for addressing challenges in investigating, assessing, and mitigating VI sites.

May 24-27, 2010 Seventh International Conference on Remediation of Chlorinated and Recalcitrant Compounds, Monterey California

Introducing the U.S. EPA Draft “Conceptual Model Scenarios for the Vapor Intrusion Pathway” Document
Lilian D. V. Abreu.

The affect of diffusion, advection, sorption and biodegradation on soil vapor and indoor air concentrations are discussed and illustrated in figures showing concentration profiles simulated with the Abreu and Johnson 3-D model for hypothetical site scenarios. The main parameters studied in this work are vapor source concentration, source depth and lateral distance from a building, soil moisture distribution in layered lithology, subsurface heterogeneities, building conditions, multiple buildings scenarios and multiple sources interactions, oxygen-limited aerobic biodegradation, and temporal and  spatial variability in subsurface and indoor air concentration.

Navy Vapor Intrusion Background Indoor Air Guidance
Loren Lund, Shahrokh Rouhani, Michael Novak, Stephen Emsbo-Mattingly, and Ruth Owens.

Provides overview of the U.S. Navy’s a new guidance document, Guidance for Environmental Background Analysis Volume IV: Vapor Intrusion Pathway. This guidance document provides instructions for characterizing and analyzing background conditions in vapor intrusion investigations.

Evaluation of Vapor Intrusion Using Controlled Building Pressure Conditions
Thomas McHugh, Daniel Bailey, Roberto Landazuri, Bart Chadwick, and Ignacio Rivera-Duarte.

Describes investigation protocol that consists of indoor air sampling under controlled negative pressure conditions followed by controlled positive pressure conditions in order to complete a definitive vapor intrusion investigation using a single 3-day field program. The observation of elevated radon concentrations in indoor air under negative building pressure conditions and atmospheric radon concentrations under positive building pressure conditions serves to confirm that the negative and positive pressure conditions successfully controlled the flow of soil gas through the building foundation. When this pattern is observed, the difference in VOC concentration in indoor air between negative and positive pressure conditions provides an accurate measure to the contribution due to vapor intrusion.

Vapor Intrusion through Sewer Systems: Migration Pathways of Chlorinated Solvents from Groundwater to Indoor Air
Charlotte Riis, Maria H. Hansen, Henrik H. Nielsen, Anders G. Christensen, and Mads Terkelsen.

Focuses on gas phase migration by advection and diffusion of chlorinated solvents into houses (near a site in Denmark) through the sewer system. The findings indicate that migration through the sewer system can be a very significant and maybe overlooked pathway for vapor intrusion. If overlooked the result may be unnoticed indoor air problems in houses located outside areas with soil and groundwater contamination.

Indoor Air Pollution: Study of Trichloroethylene Transport through Soil and Basement
Marion Musielak, Manuel Marcoux, and Michel Quintard.

Describes part of a French nationwide project (ANR Fluxobat - 2009) that aims to establish a solid procedure to determine the possible amount of pollutant in the air of a construction built above a contaminated field. Focuses on the laboratory-scale transfer of gaseous trichloroethene (TCE) through sand and concrete.

Comparison of Two Vapor Intrusion Models: What We Learned
William B. Mills and Kateryna Sayenko.

Compares the Johnson and Ettinger model to a second vapor intrusion model at sites across the United States where soil or groundwater was contaminated with VOCs.

Implementation of a Strategic Approach for Complex VI Assessment at a Large Military Facility
Emily Majcher, Paul Nicholson, Todd McAlary, David Himmelheber, Aron Krasnopoler, Robert Ettinger, Jennifer Harris, and John Wrobel.

Describes strategic approach to prioritize potential vapor intrusion risks based on historic soil and groundwater data based on a conceptual site model of the vapor intrusion pathway. Designed for a study area at Aberdeen Proving Ground, Maryland (and other large areas), where a blanket-type sampling and analysis plan (all chemicals in all media at every building) would be prohibitively expensive.

Navy’s Review of State of the Art on Vapor Intrusion Assessment
Bart D. Chadwick, Ignacio Rivera-Duarte, Todd McAlary, Robert Ettinger, Paul Johnson, Bart Eklund, Heidi Hayes.

Describes report written to identify existing best practices, knowledge and data gaps, and future research in vapor intrusion assessment strategies. The report reflects the opinion of the subject matter experts, and offers suggestions for research directions for three Navy-identified focus areas:

  • Sub-surface sampling for complete determination of the vapor intrusion pathway, which minimizes the need for intrusive sub-slab sampling
  • Passive indoor air sampling methods to improve vapor intrusion exposure estimates
  • Indoor air source separation to determine if indoor air contamination is from vapor intrusion or indoor sources

Radon Tracer as a Multipurpose Tool to Enhance Vapor Intrusion Assessment and Mitigation
Christopher C. Lutes, Robert Uppencamp, Carl Singer, Ronald Mosley, and Dale Greenwell.

Discusses the conclusions that can be drawn about vapor intrusion from various combinations of measurements, including radon concentration, volatile constituent concentration, differential pressure across a slab, and air exchange rate. Describes intensive vapor intrusion studies conducted in 2008 and 2009 in a multi-family former military townhouse complex in California and in a former industrial facility converted into residential and office space in Indiana.

Tracking Vapor Intrusion Pathways—An Active Tracer Gas Test
Per Loll, Poul Larsen, and Claus Larsen.

A tracer gas test was used to identify active pathways for vapor intrusion at polluted sites where vapor intrusion poses a risk to the indoor air quality. The test methodology was developed and tested through the Danish EPA Technology Advance Program at six field sites: four where PCE is the contaminant of concern and two where benzene is the contaminant of concern.

Vapor Intrusion Modeling: The Influence of Barometric Pressure Changes on Soil-Gas Concentrations
Annette P. Mortensen, Anders G. Christensen, Lillian D. Abreu, Lizzi Andersen, Neal Durant, and Mette Christophersen.

Uses the Abreu and Johnson model to examine the influence of barometric pressure changes on soil gas and sub-slab samples.

A New Quantitative Passive Sampler for Vapor Intrusion Assessment: The Waterloo Membrane Sampler
Hester Groenevelt, Todd McAlary, Tadeusz Górecki, Suresh Seethapathy, and Heidi Hayes.

Describes an emerging sampling technology for monitoring organic vapor concentrations that has several advantages compared to conventional methods.

Using Multiple Lines of Evidence in a Vapor Intrusion Evaluation
Amy Goldberg Day

Multiple lines of evidence were used to evaluate the source of tetrachloroethene in the air of a pet supply retailer.

Soil–Gas Sampling and Soil Vapor Intrusion: European Case Studies
Dirk Nuyens.

Presents case studies where passive soil gas sampling was combined with monitoring well installation and/or Geoprobe Membrane Interphase Probing (MIP) to evaluate the potential residential receptors at risk for vapor intrusion. Field results were used to prioritize the offsite impacted areas that would require further evaluation through ambient air sampling, and to facilitate in the external communication with stakeholders.

Radon as a Tracer for VOC Vapour Intrusion into Buildings
Boerge Hvidberg, Mette Neerup Jeppesen, and Jesper Bruun Petersen

Presents documentation for the use of radon measurements as a tracer for evaluation of vapor intrusion of VOCs from sub-slab soil gas to indoor air.

Importance of Purge Volume, Purge Rate, and Sample Volume on Soil–Gas Concentrations
James Elliot, Brian Schumacher, John Zimmerman, Greg Swanson, Blayne Hartman

Summarizes research studies conducted in May 2009 on soil gas sampling methods and variations in shallow soil gas concentrations with the purpose of improving understanding of soil gas sampling methods and data for vapor intrusion assessments and remedial planning.

Vertical Distribution of VOCs in Soils from Groundwater to the Surface/Subslab
Brian Schumacher, John Zimmerman, James Elliot, Greg Swanson, Blayne Hartman, and Curtis Callahan

Discusses research studies to assess the vertical distribution of volatile organic compounds in the subsurface, from groundwater to the surface/subslab environment. Soil gas probes were installed both underneath and adjacent to a concrete slab from just below the slab, 2' below ground surface (bgs), 4' bgs, 7' bgs, and 10' bgs. The primary contaminant was trichloroethene in the groundwater. Depth to groundwater ranged from 10 to 12' bgs.

35 Cost and Data Quality Implications in Current TO-15 Sampling Procedures
Gregory K. Shkuda, Nicole Repetti, Andrew Coenen, Christopher Domaradzki, and David Speis.

Quantitative Passive Diffusive-Adsorptive Sampling Techniques for Vapor Intrusion Assessment
Todd McAlary, Hester Groenevelt, Tadeusz Górecki, Suresh Seethapathy, Paolo Sacco, Derrick Crump, Michael Tuday, Brian Schumacher, Heidi Hayes, and Paul Johnson.

Quantitative Passive Samplers for Indoor and Outdoor Air Monitoring during Vapor Intrusion Assessments
Hester Groenevelt, Todd McAlary, Bart Chadwick, and Ignacio Rivera-Duarte.

Use of Integrated Indoor Concentrations of Tracer Gases and Volatile Organic Compounds (VOCs) to Distinguish Soil Sources from Above-Ground Sources
Ronald B. Mosley, Dale Greenwell, and Christopher Lutes.

Interval Indoor Air Measurements from a Dry Cleaner, a Residence, and at Vapor Intrusion Sites
Richard J. Rago and Gina M. Plantz.

Long-Term Integrated Samplers for Indoor Air and Subslab Soil Gas at VI Sites
Christopher C. Lutes, Robert Uppencamp, Heidi Hayes, Ronald Mosley, and Dale Greenwell.

Seasonal Variation of Soil-Gas Concentrations Near and Under a Slab Over a Year
Greg Swanson, Brian Schumacher, John Zimmerman, Blayne Hartman, and James Elliot.

Typical Spatial and Temporal Variability in VI Data Sets and Implications for Regulatory Policy
Bart Eklund.

Effect of Equilibration Time of Soil Vapor Probes on Soil-Gas Concentrations
John Zimmerman, Brian Schumacher, Greg Swanson, James Elliot, and Blayne Hartman.

High Purge Volume Tests for Managing Variability in Subslab Soil Gas
Paul Nicholson, David Bertrand, Todd McAlary, and Gordon Thrupp.

Effect of Ambient Air Quality on Soil Vapor and Indoor Air Quality R.
Joseph Fiacco, Jr., Kris Perritt, Justin Desrosier, and Jeff Gipson.

Sustainable Building Solutions to Vapor Intrusion Mitigation of Chlorinated and Recalcitrant Compounds
Ellen Moyer, John Lowe, David MacPhaul, Christy Etter, and Loren Lund.

Contaminated Site Utilizes Chemical-Resistant Vapor Mitigation Technology for Brownfield Dedevelopment
Matt Rudolph and Kelly Ameli.

Passive (Wind-Driven) Systems for Subslab Venting to Mitigate Potential Vapor Intrusion
David Bertrand, Todd McAlary, Paul Nicholson, Jackie Lanzon, and William Bingham.

November 2, 2009 Vapor Intrusion Site Issues
(Audio file and PowerPoint slides are archived on the website.)

Two-hour Webinar teaches techniques for addressing sites that have vapor intrusion issues originating from contaminated groundwater or soil. The course covers the following topics:

  • Vapor intrusion overview including current guidance from U.S. EPA, Interstate Technology Regulatory Council (ITRC), states, and the American Petroleum Institute
  • Sampling procedures for sub-slab, soil gas, indoor air, outdoor air
  • Permanent wells, temporary wells, nested wells, and sampling
  • Chlorinated VOC site: Behr Site Case Study
  • Petroleum site: Hartford Site Case Study
  • Health issues and screening levels

March 16, 2010 Update on Vapor Intrusion
U.S. EPA Workshop held at the 20th Annual Association for Environmental Health and Sciences International Conference on Soils, Sediments, Water, and Energy, San Diego, California.

Topics discussed at this workshop include background indoor air concentrations, conceptual model scenarios, lessons from radon studies and databases, community engagement, multiple lines of evidence, and mitigation.

March 15, 2010 Vapor Intrusion
Session held at the 20th Annual Association for Environmental Health and Sciences International Conference on Soils, Sediments, Water, and Energy, San Diego, California.

Presentations in this session range from vadose zone profiling, to vertical and temporal variations in sub-slab samples, to wind-driven passive mitigation

Adobe PDF LogoJanuary 12-13, 2009 National Forum on Vapor Intrusion, Philadelphia, Pennsylvania

Presentations include technical sessions covering vapor intrusion sampling and assessment, risk assessment, and engineering and site development; two breakout sessions (one for community stakeholders and one for government program issues); and a series of vapor intrusion case studies.

Cal/EPA Vapor Intrusion Workshop, June 9-10 2009, Los Angeles, California

The purpose of the workshop was to facilitate a dialogue between California EPA staff and external stakeholders regarding California EPA advisories and guidance related to vapor intrusion.

Cal/EPA Vapor Intrusion Workshop, June 3-4, 2009, Sacramento, California

The purpose of the workshop was to facilitate a dialogue between California EPA staff and external stakeholders regarding California EPA advisories and guidance related to vapor intrusion.

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