The purpose of the survey was to (1) describe material in the wells (the lithology), (2) determine the frequency, aperture, and orientation of any fractures in these materials, (3) determine the porosity, permeability, and hydraulic transmissivity of the materials, and (4) evaluate lithologic units for correlation between wells. The Butz Landfill site has been contaminated from the mid-to-late 1960's by disposal into the landfill of trichloroethene(TCE) believed to be in the form of dry cleaning fluid.
Borehole televiewer, caliper, sonic transit-time, fluid-temperature, and sonic variable-density logs were evaluated as fracture indicators. Other logs used include density, induction resistivity, spontaneous potential, single point resistance, and sonic amplitude, permeability and hydraulic transmissivity using a fractured-reservoir model provides an estimate of aquifer performance and possible contamination movement rates and direction.
Shale percentages and corrected density porosities were computed for each well. Natural gamma-ray and neutron logs were used as the primary indicators of lithologic units for correlation between wells. Due to the environment of deposition, subsequent tilting of the strata, and wide spacing of the wells, correlation of specific stratigraphic units was arduous. By splicing pieces of gamma logs from different wells, a typical gamma ray correlelation log was constructed and used to correlate large-units within the bedrock. Smaller subunit-markers were then correlated to provided better ties between wells. Calculation of formation water resistivities provides "target-zones" of possible liquid-phase Trichloroethene contamination. These zones are highlighted and potential packer-seat locations are identified for future testing.