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Research about Long Island

Source-linked reports with geographic coverage including Long Island.

At least 73 records · Page 4Linked to original sources
USGS1995

Water resources data, New York, water year 1994. Volume 2. Long Island

Water resources data for the 1994 water year for New York consist of records of stage, discharge, and water quality of streams; stage, contents, and water quality of lakes and reservoirs; and water levels and water quality of ground-water wells. This volume contains records for water discharge at 20 gaging stations; water quality at 19 gaging stations, and 32 wells; and water levels at 754 observation wells. Also included are data for 78 low-flow partial record stations. Additional water data were collected at various sites not involved in the systematic data collection program, and are published as miscellaneous measurements and analyses. These data, together with the data in Volume 1 and 3 represent that part of the National Water Data system operated by the U.S. Geological Survey in cooperation with State, Federal, and other agencies in New York

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USGS1995

Ground-water quality and geochemical processes at a municipal landfill, Town of Brookhaven, Long Island, New York

The principal geochemical process within a plume of leachate-contaminated ground water downgradient from the municipal landfill in the Town of Brookhaven is the oxidation of organic matter. Concurrent reducing processes are the reduction of iron and manganese oxyhydroxides to soluble ferrous and manganous forms, of nitrate and nitrite to nitrogen and ammonia, of sulfate to sulfide (sulfide precipitates from solution as iron and manganese sulfides), and, under extreme conditions, of some organic matter to methane. Secondary processes unrelated to bacterial activity and redox processes are the exchange of dissolved sodium and potassium for calcium and magnesium at ion-exchange sites and the dissolution of calcium and magnesium silicate minerals; these processes cause sodium and potassium concentrations to decrease with depth and with distance from the landfill and cause calcium, magnesium, and silica concentrations to increase.

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USGS1994

National Water-Quality Assessment (NAWQA) Program, Long Island-New Jersey (LINJ) Coastal Drainages Study Unit

In 1991, the U.S. Geological Survey (USGS) began its National Water-Quality Assessment (NAWQA ) program to (1) document the quality of a large, representative part of the Nation's water resources; (2) define water-quality trends; and (3) identify major factors that affect water quality. In addressing these goals, the program will produce information that will be useful to water policy makers and managers at National, State, and local levels. Studies of 60 hydrologic systems that include parts of most major river and aquifer systems form the building blocks of the NAWQA program. Study units range in size from about 1,000 mi ² (square miles) to more than 60,000 mi² and represent 60 to 70 percent of the Nation's water use and population served by public water supply. The first 20 studies were begun in 1991; 20 more were begun in 1994, and the remaining 20 are to begin in 1997.

New Jersey↗
USGS1994

National Water-Quality Assessment (NAWQA) Program, Long Island-New Jersey (LINJ) Coastal Drainages Study Unit : Scope of the Long Island-New Jersey Coastal Drainages Study-Unit investigation

Scope of the Long Island-New Jersey Coastal Drainages Study-Unit Investigation In 1991, the U.S. Geological Survey (USGS) began a National Water-Quality Assessment (NAWQA) Program to document the status of and trends in quality of a large representative part of the Nation's water resources and to provide a sound scientific understanding of the primary natural and human factors that affect the quality of these resources. The program is designed to produce long-term, consistent water-quality information that will be useful to policymakers and managers at national, State, and local levels. Investigations of 60 hydrologic systems (study units), which include parts of most major river basins and aquifer systems in the United States, are the building blocks of NAWQA. A framework has been established to ensure nationwide consistency in the approach to each study--in field and laboratory methods, in water-quality measurements, and in the supporting data requirements. Twenty studies were started in 1991, 20 more have begun in 1994, and 20 are scheduled to begin in 1997. A major design feature of the program that will facilitate integration of water-quality information at national, regional, and local scales is coordination between the individual study-unit teams and the national synthesis effort at all stages of the investigations. Thus, results that relate to various topics addressed in the study-unit investigations will be integrated smoothly into NAWQA's national synthesis component. Teams have been developed to address the following topics of national importance: pesticides, nutrients, and volatile organic compounds. These teams are investigating the specific issues by means of comparative studies of a large set of hydrologic systems distributed over a wide range of environmental settings found in the 60 study-units. The information below summarizes the goals and scope of the NAWQA Program and the Long Island-New Jersey Coastal Drainages study, which began in 1994.

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USGS1989

Hydrogeologic correlations for selected wells on Long Island, New York — A data base with retrieval program

Accurate delineation of the internal hydrogeologic structure of Long Island, NY is integral to the understanding and management of the groundwater system. This report presents a computerized data base of hydrogeologic correlations for 3,146 wells on Long Island and adjacent parts of New York City. The data base includes the well identification number, the latitude-longitude of the well location, the altitude of land surface at the well and of the bottom of the drilled hole, and the altitude of the top of the major hydrogeologic units penetrated by the well. A computer program is included that allows retrieval of selected types of data for all of, or any local area of, Long Island. These data retrievals are a valuable aid to the construction of hydrogeologic surface maps.

New York↗
USGS1988

Ground-water flow and solute transport at a municipal landfill site on Long Island, New York — Part 2: Simulation of ground-water flow

Data on the hydrogeology of a 26-sq-mi area surrounding the Brookhaven landfill site in central Suffolk County were collected as part of a hydrologic investigation of solute transport from the site. These data were used to develop a steady-state groundwater flow model of the upper glacial (water table) aquifer in the area. The model accounts for the leakage through confining units underlying the aquifer, seepage to streams, recharge from precipitation, and pumpage and redistribution of water. Refined estimates of aquifer and confining-unit properties were obtained through model calibrations. Water table altitudes generated by the calibrated model were used to determine groundwater velocities and probable flow paths in the vicinity of the site under long-term average hydrologic conditions. Groundwater velocities and probable flow paths in the study area were calculated from simulated water table altitudes generated by the calibrated flow model. Groundwater at the center of the site flows southeastward at a velocity of 1.1 ft/d. The report is the second in a three part series describing the hydrologic conditions and groundwater quality, groundwater flow, and solute transport in the vicinity of the Brookhaven landfill.

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USGS1988

Ground-water flow and solute transport at a municipal landfill site on Long Island, New York. Part 3, simulation of solute transport

A solute transport model representing a 2.3-sq mi area surrounding and downgradient from a municipal landfill site in the Town of Brookhaven, N.Y. was used to simulate migration of a conservative solute (chloride) in the upper glacial aquifer. Aquifer values used in the model were: hydraulic conductivity, 200 ft/day; effective porosity, 0.30; longitudinal dispersivity, 100 ft; transverse dispersivity, 20 ft. Average concentration of chloride was set at 875.0 mg/L in leachate and 10 mg/L in recharge and in ambient groundwater. Entry of leachate into the aquifer was assumed to have begun in 1977. Chloride concentrations in the simulated plume after 6 years of travel matched reasonably well the chloride data collected in October-December 1982. After 12 years of travel, the simulated plume extended 6,200 ft and was 2,600 ft wide. Maximum predicted concentration at the site boundary was 160 mg/L. Additional simulations were made to test the model 's ability to predict the effect of several remedial strategies on the movement of solutes. These included capping the landfill with an impermeable surface, removal of contaminated groundwater through four recovery wells, and a combination of the first two actions.

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USGS1988

Geohydrology of the Bethpage-Hicksville-Levittown area, Long Island, New York

A study of ground-water levels and flow in east-central Nassau County, N.Y. , began in October 1985. The 11.4 sqare-mile area encompasses parts of Bethpage, Hicksville, Levittown, Plainview, Plainedge, and Farmingdale. Approximately 1,200 ft of unconsolidated Cretaceous deposits and 50 to 100 ft of Pleistocene deposits overlie bedrock throughout the area. The unconsolidated deposits consist mostly of sand, gravel, silt, and clay and have good water-transmitting properties except where clay forms continuous layers that can impede groundwater flow. The area is mostly residential and industrial. Pumpage for public supply exceeds 10 million gallons per day, most of which eventually discharges from the ground-water system to tidewater as sewage outflow. Industrial pumpage during summer exceeds 10 million gallons per day, but most of the water is returned to the system through recharge basins. Ground-water levels in this area fluctuate seasonally in response to natural recharge, pumping, and use of recharge basins.

New York↗
USGS1986

Free-air gravity anomaly map of the Long Island Platform

The U.S. Geological Survey (USGS) has collected marine gravity data along the U.S. Atlantic continental margin during the last decade. This map of the Long Island platform combines the data used to make the preliminary free-air gravity anomaly map of the Atlantic continental margin (Grow and others, 1976) with the new gravity values collected aboard the RV Gilliss in 1979 and the RV Gyre in 1981. Carl Bowin provided the USNS Kealthley data from the Woods Hole Oceanographic Institution gravity data-base. We thank Bab Bowles (USGS) for his advice on editing the navigation and gravity data.

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USGS1985

Estimated public-water supply and industrial-commercial ground-water withdrawals and returns in Nassau County, Long Island, New York, 1973-79

Nassau County, New York depends upon ground water for its freshwater supply. The primary water uses are for public-water supply and industrial-commercial purposes, which together accounted for 202 Mgal/d (million gallons per day) in 1975. Public-water suppliers withdrew 85 percent of their water from the Magothy Formation. About 133 Mgal/d was returned to the ground after use in 1975, and about 69; Mgal/d was discharged to tidewater. In addition, about 34 Mgal/d infiltrated into sewerlines in 1975 and was also discharged to tidewater. Because of the importance of this freshwater supply, the New York State Department of Environmental conservation reviews applications for the installation of wells and compiles data on pumpage throughout Long Island. It also reviews applications to discharge wastewater into the surface water and ground water of the State. This report summarizes the data filed with the New York State Department of Environmental Conservation for Nassau County during 1973-79. It presents data and estimates on withdrawals for public and industrial-commercial supply, returns to the ground, and discharges through sewer systems. It also includes information on population and land use.

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USGS1983

Potentiometric surfaces on Long Island, New York -- A bibliography of maps

Historic water-level records form a major basis for ground-water investigations and water-management decisions on Long Island. Potentiometric-surface maps, one of the major sources of historic data, are scattered within the literature or are available only through the publisher or sponsoring agency. This report presents a comprehensive list of available water-table and potentiometric-surface maps from the 19th century through 1979 with the scale, years represented, and area depicted; complete bibliographic citations are included to facilitate retrieval. The bibliography is preceded by a summary of the hydrologic system and a short history of ground-water development on Long Island, with emphasis on the effects of urbanization as reflected in ground-water levels. A series of six water-table maps from before 1900 through 1979 is presented to illustrate the major historic ground-water trends. (USGS)

New York↗
USGS1982

Ground-water pumpage in Nassau County, Long Island, New York, 1920-77: Introduction and user's guide to the data compilation

Pumpage data from about 2,100 wells used for public and nonpublic water-supply in Nassau County from 1920-77 have been collected and are available for public inspection at the U.S. Geological Survey office in Syosset, Nassau County. Except for wells in use before 1920, these data constitute the entire record available through 1977. The data are divided into two categories--pumpage from wells used for public supply, and pumpage from wells used mainly for industrial and commercial uses, designated as nonpublic water supply. Pumpage is tabulated by well or well field and is given by month or year with an annual total. The report serves as an introduction and user 's manual to the data, which are available for inspection but are not included in the report because they fill several hundred pages. The report describes the method of reporting pumpage on Long Island and how pumpage values were derived from the records. It also includes well-completion data and two maps showing the location of all wells.

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USGS1981

Base flow of streams in Nassau County sewer districts 2 and 3, Long Island, New York, 1978-79

South-shore streams on Long Island, N.Y., are small, widely spaced and have few or no tributaries. Their gradients are gentle, averaging 10 feet per mile. All streams in the area studied have a mean annual discharge of less than 20 cubic feet per second, and most are from 3 to 10 miles long. Under natural conditions, about 95 percent of total streamflow originates as ground-water seepage from the upper glacial aquifer; the remaining 5 percent consists of direct runoff. Thus, the streams of Long Island function as ground-water drains, the flow of which in dry weather is controlled directly by ground-water levels adjacent to the stream channels. Monthly low-flow discharge measurements of 18 south-shore streams in Nassau County from 1978-79 are tabulated in this report. Measurement sites were established at 1,000-foot intervals between the southern tide-affected reach and the northern headwaters of each stream. The measurements provide a data base for the 'Flow Augmentation Needs Study,' supported by the U.S. Environmental Protection Agency, which will evaluate the need to replace streamflow lost through lowering of the water table as a result of sewage in Nassau County Sewer Districts 2 and 3.

New York↗
USGS1981

Hydrogeologic data from selected wells and test holes in Suffolk County, Long Island, New York, 1972-80

The population of Suffolk County, New York, an area of 922 square miles, has increased rapidly, from less than 200,000 in 1940 to about 1.3 million in 1978. Ground-water pumpage has increased from an average of 42 million gallons per day in 1950 to about 257 million gallons per day in 1978. To help supply the hydrologic information needed to anticipate and prevent shortages, this report presents hydrogeologic and well-completion data on over 700 wells and test holes.

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