Comparison of native ground-water quality with water quality in agricultural and residential areas of Long Island, New York
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Open-File Report↗
Geology topics
K.A. Pearsall
Publications and source records attributed to K.A. Pearsall.
Chlorinated organic compounds in ground water at Roosevelt Field, Nassau County, Long Island, New York
Trichloroethylene (TCE), 1,2-dichloroethylene (DCE), and tetrachloroethylene (PCE) have been detected in water from five public-supply wells and six cooling-water wells that tap the Magothy aquifer at Roosevelt Field, a 200-acre area that is now a large shopping mall and office-building complex. The cooling water is discharged after use to the water table (upper glacial) aquifer through a nearby recharge basin and a subsurface drain field. Three plumes of TCE in groundwater have been delineated--the source plume, which has penetrated both aquifers , and two more recent plumes emanating from the two discharge sites in the water-table aquifer. Concentrations of inorganic constituents in the three plumes are the same as those in ambient water in the area. The two secondary plumes discharged cooling water extended at least 1,000 ft south-southeastward in the direction of regional groundwater flow. Pumping at wells screened in the middle and basal sections of the Magothy aquifers, where clay layers are absent and sandy zones provide good vertical hydraulic connection within the aquifer system, has increased the rate of downward contaminant advection. The transient increases in downward movement are cumulative over time and have brought TCE to the bottom of the Magothy aquifer, 500 ft below land surface. (USGS)
Water-Resources Investigations Report↗
Organic compounds in ground water near a sanitary landfill in the Town of Brookhaven, Long Island, New York
Landfill leachate and groundwater near the Brookhaven landfill site were analyzed for volatile, acid-extractable, and base/neutral-extractable organic compounds classified by EPA as ' priority pollutants, ' and for dissolved organic carbon (DOC) and inorganic constituents. Thirteen priority pollutants were detected, including benzene, chlorobenzene, ethyl benzene, and naphthalene. The most commonly detected priority pollutant, benzene, was found in the landfill leachate and in five groundwater samples. The concentration of ethyl benzene was the highest of all organic compounds detected--55 micrograms/L (ug/L) in the leachate. Three samples downgradient from the site contained detectable levels of priority pollutants; two of these from wells 2000 ft downgradient from the site, contained trace amounts of chloroform, and the other, from a well 500 ft downgradient, contained four priority pollutants in concentrations totaling less than 20 ug/L. DOC concentrations ranged from 410 mg/L in the leachate to 0.8 mg/L, which is considered background level for groundwater upgradient of the landfill site. Samples from downgradient wells contained less than 8 mg/L DOC except at two wells 500 ft from the site, which contained 21 and 16 mg/L. (Author 's abstract)
Water-Resources Investigations Report↗