Geology topics
M. P. Scorca
Publications and source records attributed to M. P. Scorca.
Urbanization and recharge in the vicinity of East Meadow Brook, Nassau County, New York: Part 4 — Water quality in the headwaters area, 1988-93
Surface-water and ground-water quality in the East Meadow Brook headwaters area was monitored during 1988-93 to determine the effects of urban stormwater on water quality before, and for 1 year after, the construction of a stormwater-detention basin in 1992. Stormwater samples were collected from the stream during storms. Between storms, water samples were collected from the stream and from a network of monitoring wells in the headwaters area. The detention basin was constructed as part of a pilot project to increase aquifer recharge while decreasing the discharge of contaminated stormwater to coastal waters. Bacteria and road salt were the major contaminants detected in stormwater samples, and the concentrations of organic compounds and nutrients in the samples rarely exceeded New York State drinking-water standards. Lead and chromium were detected in only a few of the stormwater samples, and cadmium was not detected in any of the samples. Loads of most inorganic constituents in stormwater reflected the season and the magnitude of the storm and were proportional to the total stormwater volume measured at the headwaters area. Stormwater during the nonwinter (non-road-salting) season had a diluting effect on shallow ground water adjacent to the stream. Large amounts of sodium and chloride that entered the stream and ground water after road-salt applications to the Westbury drainage area affected the ground-water quality beneath and adjacent to the stream for several months. Concentrations of sodium and chloride in streamwater on March 6, 1989, reached 1,700 mg/L (milligrams per liter) and 2,700 mg/L, respectively, as a result of road salt washed in by stormwater. Median concentrations of sodium and chloride in wells in an area affected by road salt were generally several times higher than concentrations in shallow wells in unaffected suburban areas. Bromide-to-chloride ratios were used to distinguish road salt from atmospherically derived sea salt within the shallow aquifer and indicated that ground water was affected by road salt to a depth of 14 meters.
Selected hydrogeologic and water-quality data from Jones Beach Island, Long Island, New York
A data-collection site was instrumented on Jones Beach Island, a barrier island south of Long Island, N.Y., to study local freshwater/ saltwater relations in the shallow ground-water system. A geologic test boring revealed about 88 feet of well-sorted glacial outwash sand above about 15 feet of Gardiners Clay, which directly overlies silty sand of the Magothy Formation. Tidal effects on water levels in Great South Bay, the upper glacial aquifer, and the Magothy aquifer were observed and quantified with a tidal gage in the bay and analog water-level recorders in the wells.Chloride concentrations in the upper Magothy aquifer were higher than expected--about 270 mg/L (milligrams per liter), and those in the upper glacial aquifer were 17,000 to 19,000 mg/L, about the same as in Great South Bay. Estimates of pressure and freshwater equivalent heads indicate that, at the data-collection site, freshwater is discharging upward from the Magothy aquifer into the salty upper glacial aquifer, but dilution by this freshwater is undetectable. The reason for the elevated chloride concentration in the Magothy aquifer cannot be determined from available hydrogeologic information.
Ground-water quality near a scavenger-waste-disposal facility in Manorville, Suffolk County, New York 1984-85
No abstract available.