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Summary: 1
First Field Test of NAPL Detection with High Resolution Borehole Seismic Imaging
Jil T. Geller, John E. Peterson, Kenneth H. Williams, Jonathan B. Ajo!Franklin*, and Ernest L.
Majer
Earth Sciences Division, Lawrence Berkeley National Laboratory
1 Cyclotron Road
Berkeley, CA 94720
JTgeller@lbl.gov
*Department of Geophysics, Stanford University
Abstract
The purpose of this field test is to evaluate the detectability of NAPLs by high resolution
tomographic borehole seismic imaging. The site is a former Department of Energy (DOE) manufacturing
facility in Pinellas County, Florida. Cross!hole seismic and radar measurements were made in a shallow
aquifer contaminated with non!aqueous phase liquids (NAPLs). Cone penetration test (CPT) and
induction logging were performed for lithology and conductivity, respectively. The main challenge is to
distinguish fluid phase heterogeneities from anomalies arising from geologic structure. Our approach is
to compare measurements between locations of known contamination with a nearby uncontaminated
location of similar lithology where differences in signal transmission may be attributed to fluid phase
changes. The CPT data show similar lithologic structure at the locations both within and outside the
NAPL!contaminated area.. Zones of low seismic amplitude at about 7 m depth appear more extensive in
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