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Dennis J. Sulam

Publications and source records attributed to Dennis J. Sulam.

5 recordsLinked to original sources
USGS1980

Delineation of ground-water contributing areas of streams of southwest Suffolk County, New York

The hydrologic system of southwest Suffolk County consists of two major components--a deep, southward-flowing ground-water system bounded on the north by Long Islands ' regional ground-water divide and on the south by the south-shore bays and ocean, and an overlying series of shallow ground-water flow systems that are separated from one another by north-south-trending interstream water-table divides. The shallow flow systems are the source of base flow to all streams on the island. The ground-water-contributing areas of southwest Suffolk County 's 21 streams are delineated on a map. The drainage-divide locations were derived from a 1975 water-table map on the assumption that flow in the shallow flow systems is two dimensional (horizontal). This assumption is valid for the southern part of the area (adjacent to flowing streams), but, because the direction of flow in the northern part, near the regional ground-water divide, is mainly downward, the delineations for the northern part are only inferred. (USGS)

Open-File Report↗
USGS1976

Distribution and trend of nitrate, chloride, and total solids in water in the Magothy aquifer in southeast Nassau County, New York, from the 1950's through 1973

Concentrations of nitrate, chloride, and total solids in water in the Magothy aquifer, southeast Nassau County, N.Y., show a steadily increasing trend from the early 1950 's through 1973. Vertical distribution of nitrate, chloride, and total-solids concentrations as shown in cross sections of the study area indicate downward movement of these constituents from tens of feet to a few hundred feet in this time period. Maximum concentrations are in a zone underlying the areas of Westbury, Hicksville, and Plainview. Nitrate (as nitrogen) concentration increased from 4-5 mg/liter to 7 mg/liter in the area of Westbury and from 3 to 10 mg/liter in Plainview during the period 1950-73. Lowest nitrate concentrations are in the area south of a line running from North Merrick to South Farmingdale. Also, during the period analyzed (1950-73), a 10-mg/liter line of equal-chloride concentration on a cross section in the Westbury area moved downward a distance of less than 50 feet, and in the area of Hicksville, nearly 150 feet. Total-solids concentration doubled during the period 1950-73 in the area of Plainview, where maximum downward movement of pollutants was observed. (Woodard-USGS)

Water-Resources Investigations Report↗
USGS1976

Factors affecting declining water levels in a sewered area of Nassau County, New York

Double-mass-curve analysis of ground-water levels in Nassau County, Long Island, N.Y., shows that the average-weighted ground-water levels in a 32-mi 2 (83-km 2 ) segment of a sewered area declined 11.8 ft (3.6 m) relative to an adjacent unsewered area to the east during 1953-72. Electric-analog-model analysis indicates that 4.9 ft (1.5 m) of the decline is due to pumping in nearby Queens County, west of the sewered area. Most of the remaining 6.9 ft (2.1 m) of the decline is due to sewering. Streamflow within the sewered area has also declined because of the lowered ground-water levels.

New York↗