Presented By: Patricia Overmeyer, U.S. Environmental Protection Agency, Office of Brownfields and Land Revitalization

1. Patricia Overmeyer
U.S. EPA/Office of Brownfields and Land
Revitalization

2. Vapor intrusion generally occurs when there is a
migration of volatile chemicals from contaminated
groundwater or soil into an overlying building.
Volatile chemicals can emit vapors that may migrate
through subsurface soils and into indoor air spaces
of overlying buildings in ways similar to that of radon
gas seeping into homes.
Volatile chemicals may include volatile organic
compounds, select semivolatile organic compounds,
and some inorganic analytes, such as elemental
mercury, radon, and hydrogen sulfide.

4. All Appropriate Inquiries Rule
Identify conditions indicative of releases or
threatened releases of hazardous substances. (40
CFR 312.1(c))
ASTM E1527-05
Identify recognized environmental conditions – or
the presence or likely presence of any hazardous
substances or petroleum products on a property
under conditions that indicate an existing
release, a past release or a material threat of a
release…into structures on the property or inot
the ground, ground water, or surface water….

5. A Phase I Site Assessment (or AAI Investigation)
is not intended to:
• Verify or document a specific release
• Verify or document the presence of specific
contamination
• Document a specific source of a potential release
• Document the extent of a release

6.  Conditions indicative of a release that could
result in vapor intrusion, or
 Presence or likely presence under conditions
that indicate… a release that could lead to
vapor intrusion
Could be:
◦ Presence of USTs containing hydrocarbons
◦ Documentation of hydrocarbon releases at a nearby
property

7.  Goal of Phase I / AAI is not:
◦ To determine the presence of vapor intrusion (or
the presence of any other release or result of a
release)
◦ Document the presence of vapors or document
vapor intrusion events

8.  Updating EPA’s 2002 Draft Guidance on
Subsurface Vapor Intrusion
 Developing guidance on petroleum vapor
intrusion
 Hazardous Ranking System (HRS) Rulemaking
 Developing technical documents and tools

9.  Planning to issue final Subsurface Vapor
Intrusion Guidance by November 30, 2012.
 A request for public input was announced in
the Federal Register on March 17, 2011 (76
FR 14660).
 Comment period ended on May 14, 2011, all
comments received will be considered in
developing the final guidance. Comments can
be viewed at Regulations.gov (EPA-HQ-
RCRA-2002-0033).

10.  Petroleum hydrocarbons and chlorinated
hydrocarbons behave differently in respect to
VI pathway.
 The guidance will focus on
federally‐regulated (Subtitle I) UST sites,
which are typically gas stations.
 The guidance will contain information and
practices that will be useful at other sites
(e.g., fuel terminals and airport hydrant
systems) where petroleum contamination is
of potential concern.

11.  EPA is working toward a proposed rulemaking to
add a new screening component to OSWER's
Hazard Ranking System (HRS).
 Would allow sites impacted by vapor intrusion or
intrusion of other subsurface contamination to
be evaluated for placement on the Superfund
National Priorities List (NPL).
 Through this change, the HRS could directly
consider the human exposure to contaminants
that enter building structures from the
subsurface environment.

12.  The Brownfields and Land Revitalization
Technology Support Center published
Brownfields Technology Primer: Vapor
Intrusion Considerations for Redevelopment.
◦ Provides an overview of vapor intrusion and how it
can affect redevelopment.
◦ Summarizes techniques for quickly and cost
effectively assessing the potential for vapor
intrusion.

13.  Background Indoor Air Concentrations of Volatile
Organic Compounds in North American
Residences (1990 – 2005): A Compilation of
Statistics for Assessing Vapor Intrusion
◦ 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.
◦ Illustrates ranges and variability of VOC
concentrations in indoor air resulting from
sources other than vapor intrusion.

14.  EPA's Vapor Intrusion Database: Evaluation
and Characterization of Attenuation Factors
for Chlorinated Volatile Organic Compounds
and Residential Buildings
 Conceptual Model Scenarios for the Vapor
Intrusion Pathway

15. Rich Kapuscinski, Office of Solid Waste
Emergency Response
kapuscinski.rich@epa.gov
(703) 305-7411
Websites:
http://www.epa.gov/oswer/vaporintrusion/
http://www.epa.gov/oust/cat/pvi/index.htm
Patricia Overmeyer
Overmeyer.patricia@epa.gov