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D. J. Phelan

Publications and source records attributed to D. J. Phelan.

8 recordsLinked to original sources
USGS1996

Hydrogeologic, soil, and water-quality data for j-field, Aberdeen Proving Ground, Maryland, 1989-94

Disposal of chemical-warfare agents, munitions, and industrial chemicals in J-Field, Aberdeen Proving Ground, Maryland, has resulted in ground-water, surface-water, and soil contamination. This report presents data collected by the U.S. Geological Survey from Novembr 1989 through September 1994 as part of a remedial investigation of J-Field in response to the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA). Hydrogeologic data, soil-gas and soil-quality data, and water-qualtiy data are included.

Open-File Report↗
USGS1987

Water levels, chloride concentrations, and pumpage in the coastal aquifers of Delaware and Maryland

The Manokin, Ocean City, Pocomoke, and unconfined aquifers of coastal Delaware and Maryland are susceptible to saltwater intrusion from inland movement of offshore water, and from vertical leakage from the bays and deeper aquifer. Comparison of data for water levels, chloride, and pumpage affected during 1974-86 shows that, with the exception of the 44th Street area in Ocean City, Maryland, increased pumpage and lower water levels have not yet caused corresponding increases in chloride concentrations in the confined aquifers. Pumpage from shallow wells near the inland bays has caused localized saltwater intrusion into the unconfined aquifer. Chloride concentrations in the Ocean City aquifer at 44th Street increased from 50 to 200mg/L from 1976 to 1986. Chloride concentrations in water from wells in the Manokin aquifer ranged from 6 to 460 mg/L, whereas those in the Ocean City aquifer ranged from 6 to 260 mg/L. Chloride concentrations in water from the Pocomoke aquifer ranged from 5 to 46 mg/L, and from 11.5 to 46 mg/L in the unconfined aquifer. Seasonal high water levels are affected more by total annual rainfall than by pumpage. Seasonal low water levels generally have declined during most years in areas of heavy pumpage along the coast. Inland, water levels have remained about the same of year to year. (USGS)

Water-Resources Investigations Report↗