title: Post-remediation evaluation of a LNAPL site using electrical resistivity imaging.
abstract: Present understanding of the earth's subsurface is most often derived from samples at discrete points (wells) and interpolations or models that interpret the space between these points. Electrical resistivity imaging techniques have produced an improved capability to map contaminants (especially NAPLs--NonAqueous Phase Liquids) away from traditional wells using actual field data. Electrical resistivity image data, confirmed by drilling, have demonstrated that LNAPL (Light NAPL--less dense than water, such as gasoline) contaminants exist outside of a delineated and remediated area in Golden, Oklahoma. The data also demonstrate that LNAPL exists between monitoring and remediation wells which indicate low contaminant levels when sampled. Additionally, the electrical images provided the drilling location with the highest concentration of hydrocarbon ever found on the site, even after two phases of remediation work had been performed, although the sampling protocols varied. The results indicate that current methods of post-remediation site characterization are inadequate for complete site characterization.
authors.affiliation: School of Geology, Oklahoma State University, 105 Noble Research Center, Stillwater, OK, USA. halihan@okstate.edu
authors.forename: Todd
authors.initials: T
authors.lastname: Halihan
authors.forename: Stanley
authors.initials: S
authors.lastname: Paxton
authors.forename: Ivy
authors.initials: I
authors.lastname: Graham
authors.forename: Thomas
authors.initials: T
authors.lastname: Fenstemaker
authors.forename: Matt
authors.initials: M
authors.lastname: Riley
mesh_terms: D017097:Electric Impedance; D004784:Environmental Monitoring / Q000295:instrumentation / Q000379:methods*; D006838:Hydrocarbons / Q000032:analysis* / Q000633:toxicity; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity; D014872:Water Movements; D014873:Water Pollutants / Q000032:analysis* / Q000633:toxicity
chemical_list: D006838:Hydrocarbons; D012989:Soil Pollutants; D014873:Water Pollutants