U.S. Environmental Protection Agency, Region 3
Chillum Site - Gasoline Fact Sheet
Implementation of Final Remedy
September 2009

Background

EPA issued its Final Decision and Response to
Public Comments outlining the final remedy for
the gasoline release that occurred at the former
Chevron gas station previously owned by Chevron
USA, located in Chillum, Md. The release impacts
the neighboring Lamond-Riggs Park community
located in the District of Columbia (DC).

Final Remedy

Subsequent to the Final Decision on the remedy
selection, EPA issued to Chevron, USA, an
Administrative Order on Consent (AOC) which
specifies the work and the timetable upon which
Chevron must perform the required work to
implement the Final Remedy for gasoline at the
Chillum Site.

The AOC with Chevron became effective during
January 2009.

2)	EPA has approved the conceptual design plan
and implementation schedule for the Oxygen
Curtain, to be located north of Nicholson St. The
detailed design plan is projected for October 2009.
Subject to permitting, installation of the Oxygen
Curtain is projected to begin by December 2009.

3)	The Final Remedy called for the installation of
individual vapor mitigation systems in homes
located above the gasoline plume where petroleum
vapor concentrations exceeded EPA's indoor air
standards. These installations were completed in
March 2009. Testing results in other homes did
not exceed EPA's standards.

4)	EPA has approved the conceptual design plan
and implementation schedule for the Independent
Groundwater Remediation System (IGR) well
below Eastern Avenue. The detailed design plan is
projected for December 2009. Subject to
permitting approval, installation of the well is
projected to begin Spring 2010.

Current Status of Work Required by the AOC

EPA, in consultation with the D.C. Department of
the Environment has approved the conceptual
design plan and implementation schedule for the
Final Remedy.

The detailed design plan for the Oxygen
Curtain is expected by October 2009 and for the
remaining remedy components by December 2009.

The approved design for this component of the
remedy incorporates several beneficial features not
specified in the system originally selected. This
system addresses several of the concerns that
citizens raised. The IGR will not require a vent
pipe above ground, will require less space, will
operate more quietly and require less maintenance.
(See Figure Below)

2 ft

Subject to permitting from the D.C. Department of
the Environment (DDOE) and/or the Maryland
Department of the Environment (MDE) the remedy
implementation is expected to proceed as follows:

1) The existing groundwater remediation system
located on the portion of the Site within Maryland
is currently and will continue in operation;

a) The detailed design plan for expansion
of the existing groundwater remediation
system through the installation of an angle
recovery well under Eastern Avenue into
D.C. is projected for December 2009, and
subject to permit approval, installation of
the angle well is projected to begin Spring
2010.

Activated
Carbon

m

S|

Water Table

j-

II



9 ft

v&m \


-------
Site History

To view previous Fact Sheets and other
information relating to this Site go to:
http://www.epa.gov/reg3wcmd/chev7003.htm

Administrative Record

The Administrative Record, which contains EPA's
Final Remedy and the Administrative Order on
Consent issued to Chevron USA is available at:

•Lamond-Riggs Branch Library

5401 South Dakota Avenue, N.E.

Washington, D.C. 20011
202-541-6255

•U.S. EPA, Region 3

1650 Arch Street
Philadelphia, PA 19103-2029

Please call Anna Butch at 215-814-3157 to
schedule a convenient time to review the
Administrative Record.

For Additional Information Contact

Andrew H. Fan
EPA Project Manger
fan.andrew@epa.gov or
call 215-814-3426

Shawn Garvin
EPA Government Liaison
garvin.shawn@epa.gov or
call 215-814-2998


-------