Evaluation of borehole geophysical logs and hydraulic tests, phase III, at AIW Frank/Mid-County Mustang Superfund Site, Chester County, Pennsylvania

Abstract

Borehole geophysical logs, heatpulse-flowmeter measurements, and aquifer-isolation tests were used to characterize the ground-water-flow system at the AIW Frank/Mid-County Mustang Superfund Site. The site is underlain by fractured carbonate rocks. Caliper, natural-gamma, single-point-resistance, fluid-resistivity, and fluid-temperature logs were run in six wells, and an acoustic borehole televiewer and borehole deviation log was run in one well. The direction and rate of borehole-fluid movement was measured with a high-resolution heatpulse flowmeter for both nonpumping and pumping conditions in four wells. The heatpulse-flowmeter measurements showed flow within the borehole during nonpumping conditions in three of the four wells tested. Flow rates up to 1.4 gallons per minute were measured. Flow was upward in one well and both upward and downward in two wells. Aquifer-isolation (packer) tests were conducted in four wells to determine depth-discrete specific capacity values, to obtain depth-discrete water samples, and to determine the effect of pumping an individual fracture or fracture zone in one well on water levels in nearby wells. Water-level data collected during aquifer-isolation tests were consistent with and confirmed interpretations of borehole geophysical logs and heatpulse-flowmeter measurements. Seven of the 13 fractures identified as water-producing or water-receiving zones by borehole geophysical methods produced water at a rate equal to or greater than 7.5 gallons per minute when isolated and pumped. The specific capacities of isolated fractures range over three orders of magnitude, from 0.005 to 7.1 gallons per minute per foot. Vertical distribution of specific capacity between land surface and 298 feet below land surface is not related to depth. The four highest specific capacities, in descending order, are at depths of 174-198, 90-92, 118-119, and 34-37 feet below land surface. INTRODUCTION The AIW Frank/Mid County Mustang Superfund Site is in West Whiteland Township, Chester County, Pa., on U.S. Route 30 (fig. 1). The 15-acre site consists of two adjoining properties. The AIW Frank Property is at 717 East Lincoln Highway (Route 30) and the Mid-County Mustang property (currently Rex Carle Automotive) is at 891 East Lincoln Highway (Halliburton NUS, 1991). The AIW Frank Corporation occupied a small facility used to manufacture styrofoam products and commercial refrigeration units. The site is no longer active. The AIW Frank Corporation first leased the property in 1962 and purchased the property in 1975. AIW Frank operated the facility as a styrofoam products manufacturing plant from 1962 until declaring bankruptcy in 1981. AIW Frank reportedly used trichloroethylene (TCE) and 1,1,1-trichloroethane (TCA) to clean equipment. After bankruptcy, the site was bought and operated by Continental Refrigerator Corporation (CRC). From 1983 to about 1988, CRC manufactured refrigerators, freezers, and warming cabinets for the food-service industry. The front building (no longer existing) was used for manufacturing by AIW Frank and as an office by CRC. The rear building was used for warehousing by AIW Frank and for manufacturing by CRC. Solvents may have been used by CRC to clean metal components of the refrigeration units (Halliburton NUS, 1991). The U.S. Environmental Protection Agency (USEPA) requested the U.S. Geological Survey (USGS) provide technical assistance to the hydrological investigation being conducted at the AIW Frank/Mid-County Mustang Superfund Site. The USGS conducted borehole geophysical logging, aquifer tests, and aquifer-isolation tests as part of that investigation.