Region 3 GPRA Baseline RCRA Corrective Action Facility
Sunoco Partners Marketing & Terminal
(Former Mobil Oil/Tosco/ConocoPhillips Terminal)
10315 Balls Ford Road
Manassas, VA20109
Congressional District 10
EPA ID #: VAD048565279
Last Updated 1/1/06
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Current Progress at Site!
In connection with the merger between Exxon Corporation and Mobil Corporation,
Mobil Oil Corporation sold its Manassas Virginia terminal to TOSCO in early 2000.
Mobil Oil Corporation informed EPA that it continued to retain responsibility for RCRA
Corrective Action of site-wide contamination and RCRA closure of a storm water pond.
On October 11, 2000, ExxonMobil entered into a Facility Lead Agreement (FLA) with
EPA to conduct a RCRA corrective action investigation relating to contamination from
previous operations at the terminal.  In April 2001, ExxonMobil submitted a work plan to
EPA for delineation of site wide groundwater contamination. EPA approved the work
plan and the fieldwork was completed in the fall of 2001. The results were presented to
EPA and the Virginia Department of Environmental Quality (VaDEQ) in February 2002.
EPA and ExxonMobil determined that the delineation of the dissolved phase plume was
incomplete in the southwest portion of the facility. ExxonMobil agreed to add new wells
to determine whether the plume may have migrated offsite in this area. A Supplemental
Work Plan was submitted in June 2002 to EPA in which ExxonMobil proposed three
boundary wells to be installed in the southwest corner of the facility. EPA approved the
work plan and the new wells were installed  in December 2002. The sampling results
from these new wells were presented in the  Results of Site Investigation Activities and
Annual Progress Report submitted to EPA in April 2003.  Subsequently, a Work Scope
for Interim Corrective Measures and additional delineation activities in the southwest
boundary of the facility was submitted in December 2003 and approved in January 2004.
Quarterly enhanced fluid recovery and installation of three off-site wells were completed
on schedule  in 2004.

During the meeting in February 2002, ExxonMobil was advised that EPA had transferred
responsibility for the storm water pond closure to the VaDEQ.  After additional meetings
with VaDEQ, ExxonMobil submitted a Closure Plan in July 2002 and subsequent
revisions in September 2002 and 2003 in accordance with VaDEQ draft RCRA guidance.
The VaDEQ granted conditional approval of the Closure Plan in September 2003.

The three newly installed off-site wells were found to be imbedded in sound bed rock
that stay dry and groundwater samples cannot be collected.  Since none of the offsite
wells, including those previously installed, show the presence of groundwater or
groundwater contamination, EPA determines that there is no evidence of offsite plume
migration. Although the absence of evidence may not be the evidence of absence, EPA
determines that it is not productive to ask ExxonMobile to continue drill offsite wells to
prove the absence of offsite migration;  Rather, EPA requested ExxonMoble to propose
a remedy to eliminate the source of contamination  thereby mitigating the concern for
offsite migration.

In September 2005, ExxonMobil  submitted  a pilot test plan to evaluate the use of an
oxygen diffusion curtain technology to remediate the source contamination. In December
2005, EPA provided comments on the test plan and approved temporary suspension of
the Enhanced Fluid Recovery operation (tank truck vacuuming of product) that has been

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taking place quarterly.  Additionally, due to planned filling and construction on top of the
pond, EPA approved abandonment of several  monitoring wells located in the footprint of
the pond as well as closing all dry offsite wells.
Site Description
Mobil Oil Corporation owned and operated a petroleum product distribution terminal in
Manassas, Virginia until early 2000.  During a merger between Exxon Corporation and
Mobil Corporation, the terminal was  sold to TOSCO.  The facility is currently owned by
ConocoPhillips and continues to be operated for petroleum distribution. Issues at the site
include groundwater contamination and a storm water pond. Based on the discharges to
the pond from the storage tank water draw-offs that contained benzene in excess of the
toxicity characteristic regulatory level (0.5  parts per million [ppm]), Mobil filed a RCRA
Part A Application in September 1990. At the time of the Part A Application however,
the pond was subject to a National Pollutant Discharge Elimination System (NPDES)
permit. A RCRA Part B Application was submitted in September 1991. In 1994, Mobil
believed that these filings might not be necessary and attempted to withdraw both
without success. The pond was assigned EPA RCRA ID No. VAD048565279 and has
been operated consistent with interim status standards. The pond has been used for storm
water control and has been managed under an NPDES permit.  In 2005, the pond was
drained to provide access for work scheduled to be conducted on the Colonial Pipeline
delivery lines, which run immediately south of the Pond. Currently, the pond remains
dry as the facility owner has given approval by VADEQ to "clean close" the pond by
filling and use the foot print to build new oil storage tanks.
Site Responsibility
RCRA Corrective Action activities at this facility are being overseen by EPA under a
Facility Lead Corrective Action Agreement agreed to in October 2000.  VaDEQ is the
lead agency on pond closure plan review.

Contaminates
Groundwater contamination at the site consists of benzene, toluene, ethylbenzene,
xylenes and MTBE from multiple sources. An onsite pond is presently used as a storm
water management pond. However, as indicated previously, currently the pond is not
receiving rainwater collected in the tank farm or runoff from the paved areas of the
facility and the current property owner plans to use the pond area for general terminal
operations.  The pond is not considered a recreational or wildlife management area.  The
pond sampling results in 1998 showed that there was low level of PAH contamination in
the pond sediments, whereas the pond water and subsoil were clean. Evaluation of
historical data and confirmatory sediment sampling conducted in July 2003 confirmed

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that residual hazardous waste is not present in the pond. This conclusion was
documented in the Pond Characterization Summary Report submitted to the VaDEQ in
August 2003.  In September 2003, the VaDEQ concurred with the conclusions of the
Pond Characterization Summary Report. Based on this report, revisions were made to
the Closure Plan in September 2003 and were conditionally approved by the VaDEQ in
September 2003.
Community Interaction
To date, there is no community interest or involvement regarding the site contamination.
Institutional Controls

No institutional controls are currently in place.

Government Contacts
Project Manager
Mr. Andrew Fan - 3WC23
U.S. Environmental Protection Agency - Region III
1650 Arch Street
Philadelphia, PA 19103-2029
Phone: (215) 814-3426
Email: fan.andrew@epa.gov

Mr. Howard Freeland
Virginia Department of Environmental Quality
P.O. Box 10009
Richmond, VA 23240
Phone: (804) 698-4219
Email: hrfreeland@deq.virginia.gov

For more information about EPA's corrective action webpage, including Environmental
Indicators, please visit our site at: www.epa.gov/reg3wcmd/correctiveaction.htm
Facility Contact
Mr. Bruce R. Frink, P.E.
ExxonMobil Refining & Supply Company
16057 Tampa Palms Boulevard West
Suite 214
Tampa, Florida 33647
Phone: (813)991-7413
Email: bruce.r.brink(S)exxonmobil.com

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