loREiSUL    S
  SCIENCE  lies at the heart of the mission of the U.S. Environmental Protection Agency (EPA). The Agency must rely on cutting edge research, accurate
  measurements and effective technology to implement its programs to protect the environment and human health. Without sound science and credible data,
  EPA con not wisely set environmental and health standards, clean up contaminated sites, measure ambient air and water quality conditions, or identify the new
  technologies or practices that will reduce releases to the environment. These fact sheets shore with you some of"our EPA New England's laboratory capabilities
  and exemplify some of the very best science we do to meet our agency mission.
                                 GOAL:
                                 In order to support risk assessments and  clean-up decisions  at hazardous waste sites, EPA's New England
                                 Regional Laboratory conducts studies to determine levels of indoor air contamination in buildings adjacent to
                                 these sites. Regional scientists are continuing to refine and improve vapor  intrusion study methods and have
                                 expanded the use of these studies in New England in response to increased concerns about vapor intrusion and
                                 health risks to building occupants.
KEY  CONTACTS:


PETER KAHN
Environmental Engineer
(617) 918-8392
kahn.peter@epa.gov

KATRINA KIPP
Chief, Ecosystem /Assessment
(617) 918-8309
kipp.katrina@epa.gov

M ICHAEL KEN YON
Director, EPA New England
Regional Laboratory
(617) 918-8317
kenyon.michael@epa.gov
GENERAL  INFO:


EPA NEW ENGLAND
REGIONAL  LABORATORY
 I I Technology Dr.
North Chelmsford, MA 01863
(617) 918-8300
www.epa.gov/ne/lab

TOLL-FREE
CUSTOMER SERVICE
1-800-EPA-7341
PROGRESS:
Vapor intrusion is the movement of volatile organic chemi-
cals (VOCs) from contaminated groundwater and/or
soils through the ground into the air contained in overly-
ing buildings. EPA New England scientists conduct vapor
intrusion studies to investigate the extent  and severity
of contamination associated with Superfund  hazardous
waste sites. Frequently, the contamination  is  associated
with  a dry cleaning business where tetrachloroethylene
(PCE). a solvent used in the dry cleaning industry, has con-
taminated the groundwater. These chemicals are trans-
ported in the  groundwater, released as vapors, travel
through the  soil and may migrate  into  buildings where
they can adversely impact the health of occupants.

Indoor air sampling results can be misleading because it is
difficult to eliminate or adequately account  for contribu-
tions from "background" sources, including  items stored
or used by the homeowner, such as household solvents,
gasoline, and cleaning products. Therefore, a combina-
tion of soil gas, indoor air and outdoor air sampling is
necessary to make an appropriate evaluation of expo-
sure and potential health  risk to building occupants. The
laboratory's  scientists work with  the  Superfund proj-
ect manager to review existing data on contaminated
groundwater plumes, soils data, past indoor air testing
data, if available, and any other relevant information to
select properties for evaluation. The scientists then  col-
lect and analyze outdoor and indoor air samples, soil gas
samples, and vapor samples from below the basement
floor or slab (by drilling holes through the floor). EPA's
mobile laboratory conducts on-site analyses of soil gas
and air grab samples, which help refine the sampling
program as it progresses and help ensure the scientists
will not need to return to the site for more samples at
a later date. Samples are also returned to the regional
laboratory  where indoor air, ambient air and  soil gas
canister samples are analyzed to confirm field results.

Based on the findings of the laboratory's vapor intru-
sion studies, EPA takes mitigation actions to  reduce
potential  health risks.  Typically, the chemical concen-
tration levels are low, and the main concern is whether
the chemicals may pose an unacceptable  health  risk
to occupants due to  long-term exposure.  When sig-
nificant vapor intrusion is found, ventilation  is likely the
most  appropriate response option.  Affected  homes
and buildings often have soil gas mitigation  systems in-
stalled to minimize exposure to vapors from actual or
suspected water contamination incidents.

BENEFITS:
By providing timely and useful data on potential human
health risks from indoor air contamination associated
with hazardous waste sites, EPA New  England scien-
tists are  helping protect the health of affected New
England residents.
                                 <>EPA
                                                 United States
                                                 Environmental Protection
                                                 Agency
                                                                                      EPA-901-F-09-031
                                                                                             April 2009
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