For more information on Vapor Intrusion, please contact:Michael Adam
Technology Integration and Information Branch
PH: (703) 603-9915 | Email: email@example.com
Policy and Guidance
- Policy and Guidance
- Site Investigation Tools
- Community Engagement
- Conferences and Training
In 2002, EPA issued a draft guidance that provided current technical and policy recommendations on determining if the vapor intrusion pathway poses an unacceptable risk to human health at cleanup sites. The draft guidance was intended to aid in evaluating the potential for human exposure from this pathway given the state-of-the-science at the time. EPA continues to explore vapor intrusion in an effort to improve the state-of-the-science of this complex exposure pathway.
Because the approach described in the OSWER draft guidance does not account for the effects of biodegradation, its application to petroleum releases from USTs may overestimate the impact of vapor intrusion. As a result, the guidance recommends using the approach documented in the OSWER Directive Use of Risk-Based Decision Making in UST Corrective Action Programs to assess vapor intrusion at State and Regional UST corrective action sites.
In December 2009, the EPA’s Office of the Inspector General (OIG) issued a report that recommended that OSWER evaluate how the 2002 draft guidance should be updated and issue a final vapor intrusion guidance that includes recommended additions, such as multiple lines of evidence, operation and maintenance of mitigation systems, and preemptive mitigation. In addition to a Final Vapor Intrusion Guidance document, EPA is currently engaged in preparing the following vapor intrusion-related documents:
- Draft policy on how to address vapor intrusion at non-residential properties
- Guidance on using the Johnson-Ettinger model
These documents will be added to the Vapor Intrusion Focus Area when they become available (See also the EPA vapor intrusion site). EPA has already prepared several documents and tools to support development of its Final Subsurface Vapor Intrusion Guidance (*).
* Vapor Intrusion Screening Level (VISL) Calculator (MS Excel)
U.S. EPA Office of Superfund Remediation and Technology Innovation (OSRTI), 2012
The U.S. EPA Office of Superfund Remediation and Technology Innovation (OSRTI) developed a spreadsheet tool that: (1) lists chemicals considered to be volatile and sufficiently toxic through the inhalation pathway; and (2) provides VISLs for groundwater, soil gas and indoor air, which are generally recommended, media-specific, risk-based screening-level concentrations. The primary purpose of the VISL calculator is to assist Superfund site managers and risk assessors in determining, based on an initial comparison of site data against the VISLs: whether chemicals found in groundwater or soil gas can pose a significant risk through vapor intrusion; and, if so, whether a site-specific vapor intrusion investigation is warranted. Other Agency cleanup programs may also find it helpful to consider the VISLs for their own specific needs. VISL Users Guide
* EPA's Vapor Intrusion Database: Evaluation and Characterization of Attenuation Factors for Chlorinated Volatile Organic Compounds and Residential Buildings
Dawson, H.E. and R.B. Kapuscinski.
EPA 530-R-10-002, 188 pp, 2012.
This report provides updated information about the design, structure, and content of EPA's vapor intrusion database, which supersedes EPA's 2008 preliminary report on the database. Technical information is presented about sites in the United States that have been investigated for vapor intrusion. The primary focus is the evaluation of concentrations of chlorinated VOCs in and beneath residential buildings based on EPA's vapor intrusion data as of 2010. This report was peer reviewed under a different working title: U.S. EPA's Vapor Intrusion Database: Preliminary Evaluation of Attenuation Factors.
* Conceptual Model Scenarios for the Vapor Intrusion Pathway
Abreu, L. and H. Schuver.
EPA 530-R-10-003, 154 pp, 2012.
The simulation results presented in this document illustrate how different site and building conditions might influence both the distribution of VOCs in the subsurface and the indoor air quality of structures in the vicinity of a soil or groundwater VOC source. This information can help practitioners develop more accurate conceptual site models, design better sampling plans, and better interpret the results of site investigations.
* Superfund Vapor Intrusion FAQs
56 pp, February 2012.
A team of Headquarters and Regional EPA staff developed answers to a collection of Frequently Asked Questions (FAQ) about VI at Superfund sites. These FAQs provide information and recommendations based on experiences garnered over the last few years in addressing VI at Superfund remedial and removal sites and cleanups undertaken using other statutory authorities. The primary purpose of this document is to help Superfund site managers understand some of the key concepts related to assessment and mitigation of the VI pathway and to help foster appropriate consistency in technical approach. Other OSWER cleanup programs may find it helpful to consider parts of the FAQs for their own specific needs.
* Petroleum Hydrocarbons And Chlorinated Hydrocarbons Differ In Their Potential For Vapor Intrusion
U.S. Environmental Protection Agency, 13 pp, September 2011.
Discusses and compares petroleum vapor intrusion (PVI) and chlorinated solvent vapor intrusion with respect to processes that influence whether and how vapors can migrate through vadose zone materials into buildings and other confined spaces as well as some implications for addressing PVI.
* Background Indoor Air Concentrations of Volatile Organic Compounds in North American Residences (1990-2005): A Compilation of Statistics for Assessing Vapor Intrusion
EPA, 67 pp, June 2011.
Technical report presents a summary of indoor air studies that measured background concentrations of VOCs in the indoor air of thousands of North American residences and an evaluation and compilation of the statistical information reported in these studies. The objective of this compilation is to illustrate the ranges and variability of VOC concentrations in indoor air resulting from sources other than vapor intrusion.
* Indoor Air Vapor Intrusion Mitigation Approaches
49 pp, October 2008.
Engineering Issue Paper explains the range of vapor intrusion mitigation technologies available. It also provides information on selecting appropriate technologies in consultation with qualified engineering and risk management professionals. It provides information for making appropriate selections and evaluating the recommendations of mitigation contractors and engineers.
OSWER draft guidance provides technical and policy recommendations on determining if the vapor intrusion pathway poses an unacceptable risk to human health at cleanup sites. The guidance is intended to aid in evaluating the potential for human exposure from this pathway given the state-of-the-science at this time. EPA is continuing to explore this area in an effort to improve the state-of-the-science of this complex exposure pathway. An updated and final guidance on vapor intrusion is targeted for November 2012.
Assessing Protectiveness at Sites for Vapor Intrusion: Supplement to the "Comprehensive Five-Year Review Guidance"
OSWER Directive 9200.2-84, 12 pp, November 2012
This brief supplemental guidance provides recommendations for assessing VI remedy protectiveness at private and federal facility Superfund sites during the review process described in EPA's 2001 Comprehensive Five-Year Review Guidance. It also contains recommendations for assessing protectiveness at sites where a VI remedy has not been implemented and (1) the VI pathway was never adequately characterized, or (2) changes in site conditions since the last 5-year review have potentially led to a complete VI pathway. This guide lists factors relevant to VI that should be considered for each of the three major questions in the 2001 guidance: (A) Is the remedy functioning as intended by the decision documents? (B) Are the exposure assumptions, toxicity data, cleanup levels, and remedial action objectives used at the time of the remedy selection still valid? (C) Has any information come to light that could call into question the remedy's protectiveness?
Evaluation Of Empirical Data To Support Soil Vapor Intrusion Screening Criteria For Petroleum Hydrocarbon Compounds
Hers, I. and R.S. Truesdale.
EPA 510-R-13-001, 144 pp, 2013.
This report presents an evaluation of empirical data and select modeling studies of the behavior of petroleum hydrocarbon (PHC) vapors in subsurface soils at petroleum release sites and how these vapors can affect subsurface-to-indoor air vapor intrusion. Specifically, the report develops an inclusion distance approach for screening petroleum release sites for vapor intrusion that should improve the efficiency of petroleum release site investigations and help focus resources on the sites of most concern for petroleum vapor intrusion (PVI).
Directive presents the Office of Superfund Remediation and Technology Innovation’s guidance for making the operational and functional determination for vapor intrusion mitigation systems when these systems transfer to state for operation and maintenance.
Vapor Intrusion Guidebook
323 pp, October 2010.
Fact Sheet: What You Should Know About Vapor Intrusion
In addition to EPA guidance, guidance on vapor intrusion investigation and mitigation has been prepared by the Interstate Technology and Regulatory Council, the Association of State and Territorial Solid Waste Officials, and many of the state environmental regulatory agencies.
Interstate Technology and Regulatory Council
In 2007, the Interstate Technology & Regulatory Council (ITRC)─ a coalition of states, the District of Columbia, tribal and industrial representatives, and several federal partners─published Vapor Intrusion Pathway: A Practical Guideline, which is a framework intended for use with existing state and federal guidance or policy. This framework incorporates multiple lines of evidence and follows a 13-step approach to evaluating the potential for vapor intrusion. This guidance also provides detailed information on site investigation and mitigation approaches. ITRC’s companion document,Vapor Intrusion Pathway: Investigative Approaches for Typical Scenarios, walks users through using the guidance for varying scenarios, such as different contaminated properties and different receptors.
Petroleum Vapor Intrusion: Fundamentals of Screening, Investigation, and Management
387 pp, October 2014.
Vapor Intrusion Pathway: A Practical Guide
172 pp, January 2007.
Vapor Intrusion Pathway: Investigative Approaches for Typical Scenarios
52 pp, January 2007.
Association of State and Territorial Solid Waste Managers Officials
The Association of State and Territorial Solid Waste Managers Officials (ASTSWMO) developed this document to provide state federal facilities managers with a compendium of available EPA, DoD, and state regulations, policies, and guidance materials. It provides a basic understanding of available guidance and policies that aid in the incorporation of this pathway to the overall site remediation conceptual model.
State guidance, where it exists, supersedes the existing EPA guidance documents. State guidance documents range in scope and address varying issues related to vapor intrusion. Several state documents base their approach to assessing vapor intrusion on the 2002 draft OSWER guidance, but have modifications. Therefore, it is recommended that relevant state agencies be contacted concerning vapor intrusion issues to ensure appropriate guidance is followed. As more states address vapor intrusion and the science and technology behind it continues to improve, new documents are likely to be published soon and existing ones replaced. Therefore, stakeholders should contact appropriate state agencies to ensure that the most up-to-date and appropriate guidance is followed.
Available Guidance as of January 2011
- Alabama Risk-Based Corrective Action Guidance Manual
205 pp, April 2008.
- Draft Vapor Intrusion Guidance for Contaminated Sites
92 pp, July 2009
- Vapor Intrusion webpage
- Vapor Intrusion (fact sheet)
2 pp, June 2009
- Inhalation of Diesel Vapor in Indoor Air, Technical Memorandum 02-001
7 pp, 2002
- Laboratory Data Review Checklist for Air Samples
5 pp, 2010
- Soil Vapor Sampling Guidance
19 pp, July 2008
- Guidance for the Evaluation and Mitigation of Subsurface Vapor Intrusion to Indoor Air (Vapor Intrusion Guidance)
117 pp, October 2011
- California Department of Toxic Substances Control Vapor Intrusion webpage
- Advisory: Active Soil Gas Investigations
96 pp, April 2012.
- Vapor Intrusion Mitigation Advisory, Final, Revision 1
71 pp, October 2011
- Screening Model for Groundwater Contamination
last modified February 24, 2009.
- Screening Model for Soil Gas Contamination
last modified February 24, 2009.
- Guidance for Assessing Exposures and Health Risks at Existing and Proposed School Sites
Excel spreadsheet for calculating risk, updated July 12, 2006.
- Screening for Environmental Concerns at Sites with Contaminated Soil and Groundwater
Interim Final, 2005.
- Use of California Human Health Screening Levels (CHHSLs) in Evaluation of Contaminated Properties
67 pp, 2005.
- CalTOX: A Total Exposure Model for Hazardous Waste Sites
- Flow Diagram of Key DTSC Documents
1 p, August 2011
- California Indoor Air Screening Levels
26 pp, May 2013
- Petroleum Hydrocarbon Vapor Intrusion Guidance Document, Colorado Dept. of Labor and Employment, Division of Oil and Public Safety
36 pp, December 2007.
- Draft Indoor Air Guidance
58 pp, September 2004.
- Guidance for Analysis of Indoor Air Samples
9 pp, 2000.
- Policy on an Interim Risk Evaluation and Management Approach for PCE
3 pp, 2006.
- Policy on an Interim Risk Evaluation and Management Approach for TCE
2 pp, 2006.
- Petroleum Storage Tank Owner/Operator Guidance Document
45 pp, 1999.
- Proposed Revisions to Connecticut's Remediation Standard Regulations Volatilization Criteria
50 pp, March 2003.
- Connecticut Remediation Standards Regulations webpage
- Significant Environmental Hazard Condition Notification Threshold Concentrations, Reference Table A: Volatile Organic Substances
- Policy Concerning the Investigation, Risk Determination and Remediation for the Vapor Intrusion Pathway
32 pp, March 2007.
- Facts about Vapor Intrusion
- Risk Evaluation Manual
- Public Workshops for Development of the Idaho Risk Evaluation Manual for Petroleum Releases webpage
- Idaho Risk Evaluation Manual for Petroleum Releases, Draft
92 pp, January 3, 2011.
- Appendix A-7 Evaluation of the Vapor Intrusion Pathway
4 pp, January 3, 2011.
- Idaho Risk Evaluation Manual for Petroleum Releases, Draft
- Indiana Department of Environmental Management Draft Vapor Intrusion Pilot Program Guidance
90 pp, April 26, 2006.
- Supplement to IDEM's 2006 Draft Vapor Intrusion Pilot Program Guidance
26 pp, February 4, 2010.
- Use of the Johnson & Ettinger Model to Evaluate Vapor Intrusion webpage
- Louisiana Department of Environmental Quality Risk Evaluation/Corrective Action Program (RECAP)
119 pp, October 20, 2003. and
- Vapor Intrusion Evaluation Guidance
36 pp, January 13, 2010.
- Vapor Intrusion Evaluation Guidance Tables B1 - B10
13 pp, January 2010.
- Draft Indoor Air Sample Protocol with draft Indoor Air Sample Information Collection Form
8 pp, August 2, 2009.
- Draft Alternate Soil Gas Sample Point Construction and Sample Method, Utilizing
Thin Diameter Stainless Steel Tubing
5 pp, August 19, 2009.
- Draft Indoor Air and Subslab Field Sampling Checklist (1-page form)
- Draft Soil Gas Field Sample Checklist Form 2a [1-page form]
- Protocol for Collecting Soil Gas Samples, RWM-DR-026
8 pp, February 2, 2009.
- Protocol for Collecting Sub Slab Soil Gas Samples, SOP No. DR-027
7 pp, March 12, 2009.
- Soil Gas Sample Collection Method Utilizing Hand Tools, RWM-DR-005
7 pp, January 29, 2010.
- Trial Period findings from Trial Guideline for Protecting Residents from Inhalation Exposureto Petroleum Vapors
170 pp, October 1998.
- Vapor Intrusion Guidance──Interim Draft
83 pp, December 2010.
- MassDEP Indoor Air Guidance Project Blog
- Massachusetts Contingency Plan Numerical Standards: GW-2
- Indoor Air Sampling and Evaluation Guide, WSC Policy #02-430
157 pp, April 2002.
- Guidelines for the Design, Installation, and Operation of Sub-Slab Depressurization Systems,
15 pp, December 1995.
- Standard Operating Procedure for Indoor Air Contamination, SOP BWSC-07-01,
135 pp, August 2007.
- Fact Sheet: Vapor Intrusion & Indoor Air Contamination from Waste Sites (webpage)
- Vapor Intrusion Audits: Identifying and Mitigating Unacceptable Impacts to Indoor Air (webpage)
- Technical Update: Residential Typical Indoor Air Concentrations
7 pp, December 2008.
- Draft Guidance Document for the Vapor Intrusion Pathway
- Part 201 & Part 213 Cleanup and Redevelopment Program Redesign
- Vapor Intrusion Criteria and Screening Levels
- Vapor Intrusion Program Redesign Draft Flowchart
1 page, November 24, 2009.
- Vapor Intrusion Program Redesign 2009 Presentation
November 24, 2009.
- Draft Proposed Vapor Intrusion Indoor Air Criteria (IAC), Soil Gas Criteria (SGC),
and Groundwater Screening Levels (GWVISLs),
5 pp, September 24, 2009.
- Vapor Intrusion: Risks and Remedies, The Source for Part 210 and Part 213 Vapor Intrusion News
6pp, May 2010.
- Remedial and Redevelopment Division Operational Memorandum No. 1 for the Part 201
Generic Cleanup Criteria/Part 213 Risk Based Cleanup Levels,
- RRD Operational Memorandum No. 2 Sampling and Analysis - Attachment 3:
Indoor Air Designated Methods and Target Detection Limits,
7 pp, October 22, 2004.
- Technical Support Document: Part 201 Generic Soil Inhalation Criteria for Ambient Air and Part 213 Tier I Soil Inhalation Risk-Based Screening Levels for Ambient Air. RRD Operational Memorandum
No. 1, Attachment 7
35 pp, July 2007 Revision.
- Technical Support Document: Part 201 Csat Concentrations; Part 213 Tier I Csat Concentrations.
RRD Operational Memorandum No. 1, Attachment 8
15 pp, May 2007 Revision with June 27, 2007, correction.
- Technical Memorandum: Residential Soil Volatilization to Indoor Air,
Inhalation Criteria for Trichloroethylene (CAS# 79-01-6)
33 pp, September 27, 2004.
- Evaluation of the Michigan Department of Environmental Quality's Generic Groundwater
and Soil Volitization [sic] to Indoor Air Inhalation Criteria
67 pp, May 2001.
- Remediation and Redevelopment Division Program Redesign 2009: New Vapor Intrusion Criteria
and Immediate Response Activity Screening Levels
9 pp, 2009.
- Vapor Intrusion Technical Support Document, c-rem3-01
59 pp, August 2010.
- Vapor Intrusion Interior Building Survey Form, c-rem3-01a
5 pp, July 30, 2010.
- Vapor Intrusion Interior Building Survey Form, c-rem3-01a
- Vapor Intrusion Assessments Performed During Site Investigations, Guidance Document 4-01a Petroleum Remediation Program
14 pp, October 2010.
- Risk-Based Guidance for the Vapor Intrusion Pathway, c-s4-06
15 pp, September 2008.
- Background Information on the Intrusion Screening Values, c-s4-08
2 pp, September 2008.
- Background Information on the Intrusion Screening Values, c-s4-08
- Indoor Air Sampling at Vapor Intrusion Sites: Introduction, Methods, and Interpretation of Results
16 pp, February 2009.
- Volatile Organic Compounds (VOCs) in Your Home, IC#141-1381
3 pp, April 2010.
- What is Vapor Intrusion?
c-s1-06, 3 pp, June 2009.
- Intrusion Screening Values (ISVs) for Vapor Intrusion Risk Evaluation
aq1-36 [Excel spreadsheet], February 2009.
- Missouri Risk-Based Corrective Action (MRBCA) Technical Guidance, Section 6.14: Distribution of Chemicals of Concern in the Vapor Migration to Indoor Air Pathway and Appendix H: Measurement of Soil Vapor Levels
16 pp, April 2006.
- Missouri Risk-Based Corrective Action (MRBCA) Process for Petroleum Storage Tank Sites,
Appendix C: Evaluation of Indoor Inhalation Pathway (final draft),
9 pp, February 24, 2004.
- Montana Tier 1 Risk-Based Corrective Action Guidance for Petroleum Releases
28 pp, September 2009.
- Risk-Based Corrective Action (RBCA) at Petroleum Release Sites: Tier 1/Tier 2 Assessments & Reports
159 pp, May 2009.
- Nebraska Voluntary Cleanup Program Guidance
267 pp, October 2008.
- New Hampshire
- Vapor Intrusion Guidance, 58 pp, February 2013. Includes GW-2 Methodology
- New Jersey
- Vapor Intrusion Technical Guidance: Version 3.0
New Jersey Department of Environmental Protection, Site Remediation Program. 184 pp, 2013
- Vapor Intrusion Screening Levels
- Update to the VI Screening Levels
- Summary of VI Screening Level Implementation Strategy
- Flow Chart for VI Screening Level Implementation Strategy
- New Jersey Revised Johnson & Ettinger (J&E) Model Spreadsheets
- Fact Sheet: Evaluating Indoor Air Contamination Near VOC Contaminated Sites
- Fact Sheet: Subsurface Depressurization Systems
- Indoor Air VOC Sampling and Analysis Requirements
2 pp, April 2003.
- New York
- Guidance for Evaluating Soil Vapor Intrusion in the State of New York
92 pp, October 2006.
- Strategy for Evaluating Soil Vapor Intrusion at Remedial Sites in New York (DER-13)
16 pp, October 18, 2006.
- Indoor Air Sampling and Analysis Guidance
4 pp, February 1, 2005.
- Status of Vapor Intrusion Evaluations at Legacy Sites [Table]
September 14, 2010.
- North Carolina
- Vapor Intrusion Guidance
81 pp, April 2014
- Sample Collection and Evaluation of Vapor Intrusion to Indoor Air for Remedial Response and Voluntary Action Programs
114 pp, May 12, 2010.
- Closure Plan Review Guidance for RCRA Facilities
327 pp, October 2009.
- Guidance for Assessing and Remediating Vapor Intrusion in Buildings
96 pp, March 25, 2010
- Screening Model for Volatilization from Soil to Indoor Air at Heating Oil Tank Sites
- Vapor Intrusion into Buildings from Groundwater and Soil under the Act 2 Statewide Health Standard
57 pp, Effective date: January 24, 2004, Draft Section IV.A.4 of the Land Recycling Program Technical Guidance Manual. (253-0300-100)
- Vapor Intrusion
- Land Recycling Program Questions and Answers
- South Dakota
- Release Investigations and Corrective Action Requirements, Chapter 4.0 Tier Assessments
29 pp, Version 2.0, March 18, 2003.
- Addressing Vapor Intrusion at Remediation and Redevelopment Sites in Wisconsin
27 pp, December 2010 (PUB-RR-800).
- Vapor Intrusion Information
- Guidance for Professionals: Chemical Vapor Intrusion and Residential Indoor Air, Guidance for Environmental Consultants and Contractors
State of Wisconsin Department of Health and Public Services, 16 pp, February 13, 2003
- Human Health Hazards: Vapor Intrusion (fact sheet)
State of Wisconsin Department of Health and Public Services, PPH 45053, 2 pp, September 2003.
The Massachusetts Contingency Plan’s GW-2 groundwater standards (310 CMR 40.0974(2)) apply to groundwater that is considered both shallow and where there is currently a structure built on the land above the groundwater. These standards are intended to address the potential migration of volatile oil or hazardous material from groundwater into the indoor air.
The GW-2 guidelines are based on a variation of the U.S. EPA spreadsheet for the Johnson and Ettinger (1991) Model for Subsurface Vapor Intrusion into Buildings where chemical specific partitioning coefficients, subsurface properties and building parameters are used to calculate a groundwater to indoor air chemical-specific attenuation factor.
No vapor intrusion guidance available at this time.
Department of Defense
DoD Vapor Intrusion Handbook
prepared by the Tri-Service Environmental Risk Assessment Workgroup, 172 pp, January 2009.
Navy/Marine Corps Policy for Vapor Intrusion,
5 pp, April 29, 2008.
Interim Vapor Intrusion Policy for Environmental Response Actions
Department of the Army, 7 pp. November 6, 2006.
Guide for the Assessment of the Vapor Intrusion Pathway
U.S. Air Force, Institute for Operational Health, IOH-RS-BR-SR-2006-OOO1, 64 pp, February 2006.
Guidance for Environmental Background Analysis, Volume IV: Vapor Intrusion Pathway
Naval Facilities Engineering Command (NAVFAC), UG-2091-ENV, 153 pp, April 2011.
Guidance on Site Characterization for Evaluation of Soil Vapour Intrusion into Buildings
Hers, I. and J. Southwood.
Science Advisory Board for Contaminated Sites in British Columbia (SABCS), 232 pp, 2011
This guidance describes the framework, approach, and methods for sampling, chemical analysis, and data interpretation recommended for consideration by the SABCS when undertaking characterization programs at sites in British Columbia with the potential for hazardous soil vapor to migrate into indoor air.
Petroleum Hydrocarbon Vapour Intrusion Assessment: Australian Guidance
Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, 143 pp, 2013
This document provides a clear decision framework for the conduct of petroleum vapour intrusion (PVI) assessments. Drawing on guidance/science from Australia and other jurisdictions relating to the current understanding of PVI, this document outlines approaches that should be considered in the assessment of acute hazards and chronic risks, on the basis of a screening or more detailed level of assessment (as appropriate).