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Cheryl A. Klohe

Publications and source records attributed to Cheryl A. Klohe.

5 recordsLinked to original sources
USGS2007

Summary of ground-water-quality data in the Anacostia River watershed, Washington, D.C., September-December 2005

The U.S. Geological Survey, in cooperation with the District Department of the Environment (formerly the District of Columbia, Department of Health, Environmental Health Administration), conducted a ground-water-quality investigation in the Anacostia River watershed within Washington, D.C. Samples were collected and analyzed from 17 ground-water monitoring wells located within the study area from September through December 2005. Samples were analyzed for a variety of constituents including major ions, nutrients, volatile organic compounds, semivolatile organic compounds, pesticides and degradates, oil and grease, phenols, total polychlorinated biphenyls, and other selected constituents. The concentrations of major ions in the study area indicate that the ground water is predominantly calcium-bicarbonate type water, with some wells containing a higher percentage of milliequivalents per liter of iron (cation), and chloride or sulfate (anions). Concentrations of nitrogen were generally less than 1 milligram per liter, and concentrations of phosphorus were generally less than 0.5 milligrams per liter. Twelve of 79 pesticides and degradates were detected at 6 out of 17 wells. Volatile organic compounds (predominantly gasoline oxygenates and solvents) were detected in 9 of the 17 wells. Two semivolatile organic compounds, (bis(2-ethylhexyl) phthalate and total phenols), out of the 51 analyzed, were detected in the study area.

Washington DC↗
USGS2007

Hydrogeology of the Piney Point-Nanjemoy, Aquia, and Upper Patapsco aquifers, Naval Air Station Patuxent River and Webster Outlying Field, St. Marys County, Maryland, 2000–06

Recent and projected population growth in southern Maryland continues to bring ground-water-quality and quantity issues to the forefront. Lithologic, borehole geophysical, water-level, and water-use data were compiled and interpreted to revise understanding of the hydrogeologic framework of the Piney Point-Nanjemoy, Aquia, and Upper Patapsco aquifers in southern Maryland, with emphasis on the Naval Air Station Patuxent River and Webster Outlying Field. Understanding of the hydrogeologic framework for the Upper Patapsco aquifer also has been revised based on the results of aquifer testing and water-quality sampling of two wells. The Piney Point-Nanjemoy aquifer is 50 to 70 feet thick, with a top altitude of 213 to 260 feet below the North American Vertical Datum of 1988 and a hydraulic conductivity of 2 feet per day at Naval Air Station Patuxent River and Webster Outlying Field. Ground-water withdrawals from the Piney Point-Nanjemoy aquifer have been minimal since 1999 and water levels in the aquifer have not changed substantially since the 1950s. An overall decline of about 2.5 feet has been observed since 1997, however. The Aquia aquifer is 100 to 145 feet thick, with a top altitude of approximately 450 feet below the North American Vertical Datum of 1988 and a hydraulic conductivity of 6 to 10 feet per day at Naval Air Station Patuxent River. The Aquia aquifer is approximately 50 feet thick, with a top altitude of 470 feet below sea level and a hydraulic conductivity of 6 to 10 feet per day at Webster Outlying Field. Water levels in the Aquia aquifer declined in response to increased withdrawals from the aquifer from the early 1940s through about 2000 at Naval Air Station Patuxent River and Webster Outlying Field, but have been generally stable from about 1999 through April 2006. The Upper Patapsco aquifer at the Naval Air Station Patuxent River and Webster Outlying Field consists of layers of sand interbedded with layers of clay that total over 200 feet in thickness. The top of the aquifer near Naval Air Station Patuxent River and Webster Outlying Field ranges from approximately 620 to 680 feet below the North American Vertical Datum of 1988. The potentiometric surface of the Upper Patapsco aquifer near Naval Air Station Patuxent River and Webster Outlying Field has been declining at a rate of about 2 feet per year for the past several years. Aquifer testing indicates the transmissivity of the aquifer is about 2,100 to 3,900 feet squared per day. Water samples collected from the Upper Patapsco aquifer at Naval Air Station Patuxent River and Webster Outlying Field in 2000 and 2001 met all Federal drinking-water standards.

Scientific Investigations Report↗
USGS2003

Summary of water- and sediment-quality data for Anacostia River well sites sampled in July-August 2002

This data report is a summary of chemical analyses conducted by the U.S. Geological Survey on ground water and sediment in the tidal Anacostia River watershed, Washington, D.C. during July-August 2002. Cores were drilled and wells were established at three shoreline sites: two wells at the New York Avenue overpass, two wells at the Kenilworth Aquatic Gardens, and one well at Anacostia Park. Additionally, two cores were collected by hoverprobe in mudflats on the river: one by Benning Road and one in the mouth of Beaverdam Creek. Chemical analyses included volatile organic compounds, semi-volatile organic compounds or polyaromatic hydrocarbons, organochlorine pesticides, aroclors and total polychlorinated biphenyls, metals, nutrients, biochemical and chemical oxygen demands, total phenols, total cyanide, oil and grease, and total suspended and dissolved solids in aqueous phases.

Open-File Report↗
USGS2001

Occurrence and distribution of enteric viruses in shallow ground water and factors affecting well vulnerability to microbiological contamination in Worcester and Wicomico counties, Maryland

The U.S. Geological Survey, in cooperation with the Maryland Department of the Environment and the Wisconsin State Laboratory of Hygiene, conducted a study to characterize the occurrence and distribution of viral contamination in small (withdrawing less than 10,000 gallons per day) public water-supply wells screened in the water-table aquifer in the Coastal Plain in Worcester and Wicomico Counties, Maryland.Two hundred seventy-eight well sites were evaluated with regard to simulated ground-water flow paths, land use, natural soils groups, and well characteristics, such as well depth and well age. Flow and transport simulations of the water-table aquifer indicated that wells screened less than about 50 feet below land surface (shallow wells) were most vulnerable to surface contamination, which in some cases could originate from as far as 2,000 feet upgradient of the well. Animal-feeding and agricultural-storage operations were considered among the most likely sources for viral contamination; therefore, sites close to these activities were considered most vulnerable. Soil groups were evaluated with regard to depth to water and moisture-holding capacity. Wells with shallow depths to water or in very sandy soils were considered more vulnerable to contamination than deep wells (greater than 50 feet) and those completed in finer-grained soils. Older wells and wells where coliform bacteria had been detected in the past were classified as highly vulnerable. On the basis of this evaluation, 27 sites considered to be susceptible were sampled.Samples were collected by pumping up to 400 gallons of untreated well water through an electropositive filter. Water concentrates were subjected to cell-culture assay for the detection of culturable viruses and reverse-transcription polymerase chain reaction/gene probe assays to detect nonculturable viruses; grab samples were analyzed for somatic and male-specific coliphages, Bacteroides fragilis, Clostridium perfringens, enterococci, Escherichia coli, total coliforms, total oxidized nitrogen, dissolved organic carbon, organic nitrogen, total phosphate, orthophosphate, acid-neutralizing capacity, pH, specific conductance, temperature, and dissolved oxygen.Eleven percent of the samples analyzed (3 of 27) tested positive for either culturable viruses or the presence of viral ribonucleic acid. Approximately 15 percent of the samples (4 of 27) tested positive for one or more bacterial contaminants.

Water-Resources Investigations Report↗