Technology Status Report: In Situ Flushing - CLU-IN

In Situ Flushing Project Summaries
GWRTAC Case Study Database
GWRTAC ID: FLSH0041
Project Name: Texas Eastern Transmission Facil. Delmont, PA
City: Delmont State/Province: PA
Primary GWRTAC Personal
Communication Source
(Name/Organization):
Project Summary:
Fred Baldisari
Pennsylvania DEP
Report(s)/Publication(s) (GWRTAC Source):
Rice University, 1997: Technology Practices Manual for Surfactants and Cosolvents, Rice
University, 6100 Main Street, Houston, TX 77005-1892, February 1997
The following was excerpted from Rice University, 1997: Technology Practices Manual for
Surfactants and Cosolvents, Rice University, 6100 Main Street, Houston, TX 77005-1892, February
1997, which cited a July 29, 1996 Technology Report provided by S.S. Papadopulus & Associates,
Inc., and "Field Demonstration of Surfactant Injections to Enhance PCB Removal from Fractured
Rock, Delmont, PA", Main Report, S.S. Papadopulos & Associates, Inc., May 1996:
Since 1993, staff with S.S. Papadopulus & Associates, Inc. have been working at a site near
Delmont, in Westmoreland County, Pennsylvania where soils and groundwater have been
impacted by pipeline liquids containing polychlorinated biphenyls (PCBs). As part of this effort,
extensive work has been conducted in characterizing a fracture zone that passes beneath the site
and results in a spring at a distance of approximately 150 m (492 feet) downgradient of a former
pipeline liquids pit. Concentrations of total PCBs in the spring water have been measured at.
approximately 5 ug/L for the past 8 years. The spring, (SP01), has an average annual flow of
about 2.5 gpm, and discharges from a fractured zone in the sandstone bedrock underlying the
area. The geology at the Delmont site consists of interbedded sandstone, shale, clay, limestone,
and coal of the Pennsylvanian age Conemaugh Group. The local geologic structure is represented
by the lower coal unit which strikes northwest and dips 3 to 4 deg. northeast. On the hillside above
spring SP01, a few feet of overburdern overlies a sandstone unit, and the sandstone
unconformably overlies a shale unit. The water table is located within the sandstone unit, and the
spring is a discharge point for the groundwater flowing within the sandstone unit, as confirmed by
tracer studies. Average groundwater velocties of 110 to 860 feet per day, depending on the flow
rate of the spring, have been determined through tracer studies.
In an effort to explore the use of an innovative technology to remove PCBs from the fractured rock
environment and remediate the spring, two surfactant tests have been conducted at the site. Prior
to surfactant delivery, tracer tests were conducted using conservative tracers. The primary
conclusion of the tracer tests was that most of the tracer could be recovered in a period of two
weeks.
The initial test was conducted in 1993. This involved delivery of 110 gallons of cocamidopropyl
betaine (Mirataine CB) via a monitoring well located near the pipeline liquids pit. The net effect of
this effort was to increase PCB concentrations at the spring from 5 to approximately 260 ug/L. The
Ground-Water Remediation Technologies Analysis Center
Operated by Concurrent Technologies Corporation
Appendix - Page 83 of 164
Copyright GWRTAC 1998
Revision 1
Tuesday, November 17, 1998