Geologic and hydrologic data were collected at Wright-Patterson Air Force Base (WPAFB), Ohio, as part of Basewide Monitoring Program (BMP) that began in 1992. The BMP was designed as a long-term project to character ground-water and surface-water quality (including streambed sediments), describe water-quality changes as water enters, flows across, and exits the Base, and investigate the effects of activities at WPAFB on regional water quality.
Ground water, surface ware, and streambed sediment were sampled in four rounds between August 1993 and September 1994 to provide the analytical data needed to address the objectives of the BMP. Surface-water-sampling rounds were designed to include most of the seasonal hydrologic conditions encountered in southwestern Ohio, including baseflow conditions and spring runoff. Ground-water-sampling rounds were scheduled for times of recession and recharfe.
Ground-water data were used to construct water-table, potentiometric, and vertical gradient maps of the WPAFB area. Water levels have not changed significantly since 1987, but the effects of pumping on and near the Base can have a marked effect on water levels in localized areas. Ground-ware gradients generally were downward throughout Area B (the southwestern third of the Base) and in the eastern third of Areas A and C (the northeastern two-thirds of the Base), and were upward in the vicinity of Mad River. Stream-discharge measurements verified these gradients.
Many of the U.S. Environmental Protection Agency maximum contaminant level (MCL) exceedances of inorganic constituents in ground water were associated with water from the bedrock. Exceedances of concentrations of chromium and nickel were found consistently in five wells completed in the glacial aquifer beneath the Base. Five organic compounds [trichloroethylene (TCE), tetrachloroethylene (PCE), vinyl chloride, benzene, and bis(2-ethylhexyl) phthalate] were detected at concentrations that exceeded MCLs; all of the TCE, PCE, and vinyl chloride exceedances were in water from glacial aquifer, whereas the benzene exceedance and most of the bis(2-ethylhexyl) phthalate exceedances were in water from the bedrock. TCE (16 exceedances) and PCE (11 exceedances) most frequently exceeded the MCLs and were detected in the most samples.
A decrease in concentrations of inorganic and organic compounds with depth suggest that many constituents detected in ground-water samples are associated partly with human activities, in addition to their natural occurrence. Included in the list of these constituents are nickel, chromium, copper, lead vanadium, zinc, bromide, and nitrate. Many constituents are not found at depths greater than 60 to 80 feet, possibly indicating that human effects on ground-water quality are limited to shallow flow systems. Organic compounds detected in shallow or intermediate-depth wells were aligned mostly with flowpaths that pass through or near identified hazardous-waste sites.
Few organic contaminants were detected in surface water. The only organic compound to exceed MCLs for drinking water was bis(2-ethylhexyl) phthalate, but it was detected at concentrations just above the MCL. Inorganic constituents detected at concentration exceeding MCLs include beryllium (twice), lead (once), thallium (once), and gross alpha radiation (once). No polycyclic aromatic (PAHs) were detected in surface-water samples. The highest concentrations of contaminants detected during a storm event were in samples from upgradient locations, indicating that off-Base sources may contribute to surface-water contamination.
Inorganic and organic contaminants were found in streambed sediments at WPAFB, primarily in Areas A and C. Trace metals such as lead, mercury, arsenic, and cadmium were detected at 16 locations at concentrations considered 'elevated' according to a ranking scheme for sediments. PAHS were the organic compounds detected most frequently and in highest concentrations organo
Additional Publication Details
USGS Numbered Series
Results of the basewide monitoring program at Wright-Patterson Air Force Base, Ohio, 1993-1994
Water-Resources Investigations Report
U.S. Geological Survey ;
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