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Problem The Village of Dryden, rural homeowners, farms, and businesses in the Virgil Creek Valley tap several confined sand and gravel aquifers in the Virgil Creek valley in the town of Dryden . The valley contains a large moraine with complex stratigraphy consisting of continuous and discontinuous layers of till, lake deposits, and glaciofluvial sand and gravel. Sand and gravel units form the aquifers in the valley-fill deposits. There are at least three extensive confined aquifer units at various depths. However, little is known about (1) the location of recharge and discharge areas, (2) direction of groundwater flow, (3) extent of hydraulic connection between aquifer units, and (4) extent of surface- and ground-water...
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Summary The U. S. Geological Survey (USGS) will conduct simulations using existing aquifer data, including geologic logs from vertical profile borings (VPBs) and well installations, water levels, and pump test data available from the water districts for these production wells. Subsequently USGS will incorporate data from a groundwater pump test and additional data from new VPBs and monitoring wells. Using particle tracking maps, USGS will illustrate the spatial configuration of the capture zone and percentage of capture of the shallow and deep plumes in each production well. The model area will be limited to achieve these objectives and make maximum use of available sampling locations in the region. USGS will...
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Background The North Atlantic Coastal Plain (NACP) covers a land area of approximately 34,000 mi 2 along the eastern seaboard of the United States from Long Island, N.Y., southward to the northern portion of North Carolina. This area is underlain by a thick wedge of sedimentary deposits that form a complex groundwater system in which the sands and gravels function as confined aquifers, and the silts and clays function as confining units. These confined aquifers of the NACP constitute a major source of water for public and domestic supply for the nearly 27 million people living in the region, as well as being important source of water for industrial and agricultural purposes. Increases in population and...
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Introduction High nitrate concentrations are a common concern among many purveyors, including the Suffolk County Water Authority (SCWA), the largest supplier of water to residents in Suffolk County. Typically, the amount of nitrate in groundwater is related to land use, where the greatest concentrations are observed in agricultural regions. In many areas, the nitrate concentration has increased steadily in recent years, even in areas that are no longer farmed and are now sewered. A statistical analysis for trends of over 20 years in nitrate concentration data from SCWA wells is needed to determine the susceptibility of supply-wells to exceed the Maximum Contaminant Level (MCL) for nitrate. This information is essential...
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Water-management alternatives being considered for New York City involve aquifer storage and recovery, or ASR. An ASR system may store surplus water in an aquifer, then later recover this water in times of short supply. The success of an ASR system depends on the quantity and quality of water that can be withdrawn during recovery phases, which are influenced by hydrogeologic, microbiological, and geochemical factors. Mixing surface waters with ambient ground waters within a deep confined aquifer may cause freshwater/saltwater interface movement, clay swelling, mineral dissolution, new patterns of bacterial growth, and other hydrogeologic consequences. In 2005, data were collected at Tottenville, Staten Island,...
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Groundwater in the Newark basin aquifer flows primarily through discrete water-bearing zones parallel to the strike and dip of bedding, whereas flow perpendicular to the strike is restricted, thereby imparting anisotropy to the groundwater flow field. The finite-element model SUTRA was used to represent bedrock structure in the aquifer by spatially varying the orientation of the hydraulic conductivity tensor to reflect variations in the strike and dip of the bedding. Directions of maximum and medium hydraulic conductivity were oriented parallel to the bedding, and the direction of minimum hydraulic conductivity was oriented perpendicular to the bedding. Groundwater flow models were prepared to simulate local flow...
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Fire Island National Seashore (FIIS) is located on the barrier island along the extreme southern shore of western and central Suffolk County, New York. Interspersed throughout FIIS are seventeen residential beach communities that in the summer months greatly increase in population due to the arrival of summer residents and vacationers. Wastewater from the numerous homes and businesses in the barrier island communities generally is discharged directly into the shallow ground-water system through use of private septic systems. Contaminants entering the ground-water system can pose a threat to coastal habitats, as they are transported by ground water that discharges to ocean and estuary shorelines. In October 2004,...
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Problem - Roof collapses in the Retsof salt mine near Geneseo N.Y. in March and April of 1994 propagated upward through overlying bedrock, forming a 600-ft-long rubble zone or chimney that connected the mine to a glacial aquifer system and created sinkholes at land surface. Fresh water from the glacial aquifers flowed downward into the mine until the mine was completely flooded in January 1996. The mine opening is predicted to slowly close over a period of several hundred years, with most of the subsidence occurring before 2070. As the mine opening closes, about 40 percent of the brine will be displaced from the mine and migrate upward through the rubble chimney. Continuing monitoring of chloride concentrations...
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Problem - The Tug Hill glacial aquifer is a 47-mile long, sand and gravel deposit that occupies 103 mi2 along the western side of the Tug Hill Plateau in northern New York. The northern part of the aquifer is designated a sole-source aquifer by the U.S. Environmental Protection Agency. The aquifer is a relatively shallow, unconfined system that readily interacts with streams that flow over it. These streams, sustained by groundwater discharge, are the premier steelhead trout-producing streams in the Lake Ontario basin in New York State. A number of villages and most private homeowners get their water from the aquifer, and recently other industries, including a proposed bottled-water plant, could add to withdrawals...
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Summary Fire Island National Seashore (FIIS) occupies 42 km of the barrier island for which it is named that lies off the southern shore of western and central Suffolk County, Long Island, N.Y. Fire Island is underlain by a complex aquifer system consisting of unconsolidated glacial, lacustrine, deltaic, and marine deposits of clay, silt, sand, and gravel that range in age from Late Cretaceous to Holocene. Accelerated sea level rise, storms, rising temperatures, and changes in patterns of precipitation are all expected to drive significant ecological change. Among the most vulnerable resources are the Island’s fresh groundwater resources. The potential for climate-driven changes in the quantity and quality of...
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Problem The ground-water flow system underlying the Manhasset Neck Peninsula, which provides potable water to the local population, consists of a complex assemblage of Pleistocene- and Cretaceous-age sediments that form five aquifers and at least two confining units. Recent hydrogeologic mapping in Manhasset Neck indicates significant glacial erosion of the Magothy aquifer, Raritan Clay, and Lloyd aquifer, and several gaps in the confining units that overlie the North Shore and Lloyd aquifers. Five areas of salt-water intrusion have been delineated, two of which are considered active. Several public-supply wells on the Manhasset Neck Peninsula have been shut down in the past as a result of saltwater intrusion....
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Problem - Increasing development within the Shenandoah Valley in recent years has placed additional demands on the region’s water resources. The sedimentary rocks in the Valley have been compressed and folded by tectonic forces to form a 5-km deep basin. Ground water, a principal component of the available water supply, flows through fractures in the sedimentary and crystalline rocks that underlie the Valley. Bedding fractures in the rocks are angled downward along the dip of the folds, allowing ground water to penetrate deeply below land surface—fresh water is obtained from wells over 800 ft deep in the Valley. Objectives - Develop a ground-water-flow model to simulate movement of ground water and estimate...
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Problem Long Island’s sole-source aquifer system, which includes the Lloyd, Magothy, Jameco, and upper glacial aquifers, supplies groundwater to over 2.8 million people. As a coastal aquifer system, it is susceptible to saltwater intrusion. Past pumpage and sewering (fig. 1) resulted in increased salinity in most aquifers in all counties (Buxton and Shernoff, 1999; Misut and others, 2004; Misut and Aphale, 2014). Simulation of drought has predicted increasing salinity in the lower part of the glacial aquifer of the North Fork of Suffolk County (Misut and others, 2004). In addition, simulation of future well pumpage in Queens County by the U.S. Geological Survey (USGS) has predicted increasing salinity in the...
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Problem - Several supply wells in Oswego County were evaluated by the USGS in 1999 by using stable oxygen and hydrogen isotopes and chlorofluorocarbon (CFC) age dating techniques. For two municipal well sites (the Villages of Sandy Creek and Lacona, and the Village of Pulaski) that tap a shallow, unconfined aquifer (typically 20-50 ft thick) there were significant discrepancies between ground-water recharge ages determined by chemical data and those determined by ground-water-flow models developed by independent studies. The significant discrepancies between the times of travel of ground water as determined by numerical ground-water-flow modeling and geochemical dating techniques in Oswego County need to be understood...


    map background search result map search result map Simulation of the Shallow Ground-Water Flow System at Fire Island National Seashore, Long Island, New York Simulation of Ground-Water Flow and Chemistry to Evaluate Water-Management Alternatives in Kings and Queens Counties, New York Ground-water-flow model of the Shenandoah Valley, Virginia and West Virginia Simulation of migration of brine and saline water from the flooded Retsof salt mine in the Genesee Valley, New York Trends in Nitrate Concentrations in Public Water-Supply Wells, Suffolk County, New York, 1982-2008 Assessment of Groundwater Resources to Adapt to Climate Change at Fire Island, New York Simulation of Zones of Groundwater Contribution to Three Well Fields Southwest Portion of the Naval Weapons Industrial Reserve Plant, Bethpage, New York Development of a Ground-Water Flow Model for the Manhasset Neck Peninsula, Nassau County, New York Hydrogeology of the Virgil Creek Valley in the Town of Dryden, Tompkins County, New York Hydrogeology of Two Areas of the Tug Hill Glacial-drift Aquifer, Oswego County, New York Hydrogeology, Water Quality, and Simulation of Groundwater Flow in the Tug Hill Glacial Aquifer in Jefferson, Oswego, and Oneida Counties, New York Groundwater Availability of the Northern Atlantic Coastal Plain Hydrogeology and Simulation of Groundwater Flow in Fractured Rock in the Newark Basin, Rockland County, New York Delineation of the Hydrogeologic Framework and Saltwater-Freshwater Interface and Determination of Water-Supply Sustainability of Long Island, New York Simulation of Zones of Groundwater Contribution to Three Well Fields Southwest Portion of the Naval Weapons Industrial Reserve Plant, Bethpage, New York Hydrogeology of the Virgil Creek Valley in the Town of Dryden, Tompkins County, New York Development of a Ground-Water Flow Model for the Manhasset Neck Peninsula, Nassau County, New York Hydrogeology and Simulation of Groundwater Flow in Fractured Rock in the Newark Basin, Rockland County, New York Simulation of migration of brine and saline water from the flooded Retsof salt mine in the Genesee Valley, New York Simulation of the Shallow Ground-Water Flow System at Fire Island National Seashore, Long Island, New York Assessment of Groundwater Resources to Adapt to Climate Change at Fire Island, New York Simulation of Ground-Water Flow and Chemistry to Evaluate Water-Management Alternatives in Kings and Queens Counties, New York Hydrogeology, Water Quality, and Simulation of Groundwater Flow in the Tug Hill Glacial Aquifer in Jefferson, Oswego, and Oneida Counties, New York Hydrogeology of Two Areas of the Tug Hill Glacial-drift Aquifer, Oswego County, New York Trends in Nitrate Concentrations in Public Water-Supply Wells, Suffolk County, New York, 1982-2008 Delineation of the Hydrogeologic Framework and Saltwater-Freshwater Interface and Determination of Water-Supply Sustainability of Long Island, New York Ground-water-flow model of the Shenandoah Valley, Virginia and West Virginia Groundwater Availability of the Northern Atlantic Coastal Plain