Technology Status Report: In Situ Flushing - CLU-IN

In Situ Flushing Project Summaries
GWRTAC Case Study Database
GWRTAC ID: FLSH0012
Project Name: General Motors NAO Research & Development Center, Warre
City: Warren State/Province: MI
Primary GWRTAC Personal
Communication Source
(Name/Organization):
Project Summary:
None
None
Report(s)/Publication(s) (GWRTAC Source):
Ground-Water Remediation Technologies Analysis Center (GWRTAC), 1996: Technology
Evaluation Report TE-96-002, Surfactants/Cosolvents, Dr. Chad T. Jafvert, Purdue University,
GWRTAC, 320 William Pitt Way, Pittsburgh, PA, available at www.gwrtac.org
Rice University, 1997: Technology Practices Manual for Surfactants and Cosolvents, Rice
University, 6100 Main Street, Houston, TX 77005-1892, February 1997
U.S. Environmental Protection Agency (EPA), April 1995: Status Report: Surfactant
Enhancements, EPA 542-K-94-003, U.S. EPA OSWER (5102W), TIO, Washington, DC
The following was excerpted from U.S. Environmental Protection Agency (EPA), April 1995:
Status Report: Surfactant Enhancements, EPA 542-K-94-003, U.S. EPA OSWER (5102W), TIO,
Washington, DC, and GWRTAC, 1996: TE-96-002, Surfactants/Cosolvents, Jafvert, Purdue U,
avail. at www.gwrtac.org:
Following laboratory evaluations of a surfactant washing technique, researchers conducted a twophase
field test of an in situ surfactant washing method at a site contaminated with polychlorinated
biphenyls (PCBs) and oils. Feasibility studies were also conducted on the use of ultrafiltration to
recover surfactant from aqueous waste streams generated from the in situ surfactant washing. The
field test site was used to store unused machinery and the contamination is confined to the upper
15 feet of the subsurface fill material. A containment wall of clay and cement was previously
installed around the five-acre site. This wall extends to a depth of 60 feet below the surface. A
surfactant solution was applied via vertical infiltration to a test plot 10 feet in diameter and five feet
deep, for 70 days. The leachate was collected with a recovery well installed through the center of
the plot. The leachate pumped to the surface was biotreated to degrade the oils and surfactant
while the PCBs were recovered from the leachate by an activated carbon system. Soil cores from
the site showed initial concentrations of up to 6,000 ppm PCBs and 67,000 ppm oils. In separate
tests, leachate from the surfactant washing demonstration was collected in a process tankand
pumped into a Romicon Model HF-Lab-5 ultrafiltration unit equipped with either of two membranes
(XM50 and PM500) to evaluate the recovery of the surfactant from the leachate for possible reuse.
About 10% of the contaminants were recovered after 5.7 pore volume washings during the phase 1
field test. During a similar phase 2 test the following year, an additional 14% was recovered after
2.3 pore volumes. The results from the second phase of the field study surpassed the prediction of
the long-term perfomance of this technology based on the phase 1 results and confirmed the
Ground-Water Remediation Technologies Analysis Center
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Appendix - Page 23 of 164
Copyright GWRTAC 1998
Revision 1
Tuesday, November 17, 1998