LANTRY OIL
CHEYENNE RIVER INDIAN RESERVATION
LANTRY, SOUTH DAKOTA
March 2009
ACCOMPLISHMENTS
• Conducted site investigations
• Installed 16 MWs
• Ground-water monitoring
• Evaluated potential indoor air exposure pathways
• Performed AS/SVE pilot study
• Evaluated technical and economic feasibility of SVE
system as remedial strategy
• Evaluated MNA as remedial strategy
• Designed and installed full-scale SVE system
• Operated and Maintained SVE system
EPA Region 8 performed this work in partnership with
the Cheyenne River Sioux Tribe and with contract sup-
port from Avanti Corporation.
PLANNED ACTIVITIES/
FUTURE STRATEGIES
• In-situ chemical oxidation (ISCO) injections to fur-
ther remediate the contamination
• Groundwater monitoring
• Continued operation and maintenance of the SVE
system
SITE HISTORY
In 1993, 2-2,000 gallon diesel oil underground stor-
age tanks (USTs) and 1-550 gallon gasoline UST were
removed from the site. State of South Dakota inspectors
reported that petroleum odors and soil contamination
at the bottom of the tank pit were present when the
USTs were removed. Sampling and laboratory analysis
of samples taken from the site indicated contamination
of BTEX, naphthalene, and TPH. In 1997, the site
became eligible for federal leaking underground storage
tank (LUST) funding. Monitoring wells (MWs) were
installed at the site to determine the extent of the con-
tamination, exposure pathways, and risk to receptors.
Indoor air samples also were collected in the on-site
buildings. In 2005, an air sparge/soil vapor extraction
(AS/SVE) pilot study was conducted. An analysis of
the pilot test concluded that AS/SVE remediation was
economically and technically feasible for remediation of
the soil and groundwater contamination at the site. After
evaluation of the pilot study data and monitored natural
attenuation (MNA) as remediation alternatives, it was
determined that the installation of a SVE system would
be the most viable remediation option for the site. A full
scale SVE system was designed and installed at the site.
The SVE system was tested and became operational
in June 2008. The system specifically targets residual
hydrocarbons from the vadose zone. It was determined
that contaminant impacts to groundwater also will be
mitigated over time as the contributing source of hydro-
carbons in the soils is reduced. This was the first SVE
remediation system installed in EPA Region 8.
•
Lantry
VIE LINE
V 1 L_ !_ Ill !_»
2-2,000 gallon diesel USTs
and 1-550 gallon gasoline UST
were removed
Site investigation
5 MWs installed
Groundwater
monitoring
•
i
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
Federal LUST funding eligibility determination '
Site characterization to determine pathways
Evaluation of AS/SVE pilot
Site investigation of indoor
air exposure pathways
study data « MNA evaluation
Recommendation that SVE be
used as the remedial strategy
2002 2003 2004 2005 2006 2007 2008 2009 2010 B
AS/SVE pilot study 1
Design, installation and
Operation and
maintenance of
the SVE system
jr "*»_
(SB)
start-up of SVE system
nibLdiieu " uruuriuwdier murmuring
LANTRY OIL
EPA Region 8 UST Program Technical Contact | Mr. Raymond Faliskie | (303) 312-6124 or faliskie.raymond@epa.gov | www.epa.gov/region8/ust/
------- |