Remediation by 2-PHASETM Extraction--A 2-Year Success Story
Chris Koerner, James Siegfried, James Baxter, and Scott
Huber
Radian has used the Xerox 2-PHASETM Extraction technology at
several facilities worldwide to remove VOCs and petroleum hydrocarbons from
subsurface soils and groundwater. The use of high vacuum with 2-PHASETM
causes greater forces to be applied to the subsurface than do other dual-phase
methods. 2-PHASETM improves dewatering, increases vacuum and
groundwater radii of influence, deepens vadose zone development, enhances vapor
stripping of soil
contamination, improves vapor flow, and expedites remediation
timeframes.
This paper describes the successful 2-year application of 2-PHASETM
to remediate soil
and several groundwater contamination. Contamination occurred
under a floor slab near a former solvent spray booth and several underground
storage tanks. Contaminants were primarily chlorinated VOCs and mineral spirits
ranging to 330 mg/kg in
soil
and 1,070 mg/L in groundwater. The 2-PHASETM
system was installed in October 1993; business constraints necessitated the
completion of remediation within two years. The system was modified and expanded
to optimize the removal effectiveness and extend the area of influence.
Subsurface
soil
data obtained 8 and 11 months into the remediation program were
used with
soil
gas data to predict future
soil
concentrations. VOC
concentrations in he
soil
and groundwater were reduced by over 95 percent, and
remediation goals were met within 18 months following start of in situ 2-PHASETM
remediation. The system has been decommissioned following agency and landowner
approval.
AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California