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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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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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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 The success of an ASR system depends on the quantity and quality of water that can be withdrawn during recovery phases, which are influenced by hydrogeologic, microbiological, and geochemical factors.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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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 changes...
Categories: Data, Project; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Cooperative Water Program, Delaware, Focused Assessments, Focused Assessments, Focused Assessments, All tags...
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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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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...
Categories: Data, Project; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Contaminants, Natural, Contaminants, Natural, Contaminants, natural, Cooperative Water Program, GW Model, All tags...
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Background and Problem Tully Valley is part of the Onondaga Trough, which extends from the Valley Heads Moraine in the south to Onondaga Lake in the north near Syracuse, New York (fig. 1). The Onondaga Trough is filled with a complex sequence of glacial and post-glacial sediments that overlie Devonian carbonate rock and shale and Silurian shale and salt (fig.2). Mudboils, volcano-like cones of fine sand and silt, have been documented in the Tully Valley since the late 1890s, and have been continuously discharging turbid water into Onondaga Creek since the 1950s (Kappel and others, 1996). Continuous mudboil activity appears to be correlated with salt solution-mining activities in brine fields at the southern...
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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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Background For effective wellhead protection, the area where water carrying potential contaminants can enter the groundwater system and flow to the supply well must first be defined, and then best management practices need to be implemented to minimize the opportunity for contamination to occur in areas defined as sources of water to the well. Determination of the sources of water and contributing areas to wells is complex because aquifers and their connection with recharge sources are heterogeneous in nature and hidden from direct observation. The major groundwater source for public supplies in upstate New York are valley-fill aquifers of glacial and post-glacial origin. Saturated coarse-grained sediments (sand...
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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: Dissolved volatile-organic compounds (VOCs), including trichloroethylene (TCE), have been identified in a sole-source aquifer near the former Northrop Grumman Bethpage facility and Naval Weapons Industrial Reserve Plant (NWIRP) in Nassau County, N.Y. The Northrop Grumman Bethpage facility and NWIRP are listed as Class II inactive hazardous waste disposal sites (Site Nos. HW130003A and HW130003B respectively) on the New York State registry of Inactive Hazardous Waste Disposal Sites. Past investigations have documented that the groundwater contamination originated from these two sites and now extends nearly four miles to the south; in the direction of groundwater flow. During 2019, a groundwater-flow model...
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The data contained in this data release support USGS Scientific Investigations Report 2020-5023, "Distribution of selected hydrogeologic characteristics of the upper glacial and Magothy aquifers, Long Island, New York" (Walter and Finkelstein, 2020). This data release contains estimates of aquifer texture describing the Long Island aquifer system. These estimates in total can be considered a model of aquifer texture describing unconsolidated sediments in the following principal units: 1) Upper glacial aquifer, 2) Jameco aquifer, 3) Monmouth Greensand confining unit, and 4) Magothy aquifer. The Lloyd aquifer, a major aquifer on Long Island, is not included in the model due to a lack of available data. Aquifer texture...
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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 entire Tug Hill glacial aquifer is a 47-mile-long, crescent-shaped mixture of glacial deposits of predominantly sand and gravel on the western side of the Tug Hill Plateau in Jefferson, Oswego, and Oneida Counties in north central New York. The Tug Hill aquifer can be divided into three parts (northern, central, and southern) based on geohydrological setting, depositional history, and type of glacial deposits (fig. 1). In this study, the name “Tug Hill glacial aquifer” refers only to the 29-mi-long northern and central parts of the Tug Hill aquifer. (The southern part was not included in this investigation.) For this study, the division between the northern and central parts of the aquifer was placed...
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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....
Categories: Data, Project; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Complete, Completed, Cooperative Water Program, GW Model, GW Model, All tags...
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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 the...
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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 Magothy...
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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...
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Problem The Peconic Estuary of eastern Long Island, New York, is undergoing development as the region transitions from a rural area dependent on agriculture and tourism to a suburban one with a larger year-round population. The glacial and coastal-plain sediments underlying Long Island comprise a sole-source aquifer system that supplies the region’s communities with potable water. The area surrounding the Peconic Estuary was intensely farmed prior to suburbanization. Nitrogen loading from past fertilizer use was high as estimated from historical information and the continued detection of legacy effects in the aquifer system. In some areas, the peak or bolus of agricultural nitrogen loading from practices several...


    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 Geohydrology and Water Quality of the Northern and Central Parts of the Tug Hill Glacial Aquifer, Jefferson and Oswego Counties, North Central 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 The Use of Solute-transport Methods to Estimate Time-varying Nitrogen Loading Rates to the Peconic Estuary Resulting from Wastewater and Fertilizer Inputs to Groundwater in Suffolk County, New York (Peconic Solute Transport) Simulation of Contributing Areas to Selected Public Water-Supply Wellfields in the Valley-Fill Aquifers of New York State Aquifer texture data describing the Long Island aquifer system Determination of Sources of Water to the Tully Valley Mudboils Analysis of Factors Affecting Plume Remediation in a  Sole-Source Aquifer System, Nassau County, New York (Northrup Grumman Plume) Simulation of Zones of Groundwater Contribution to Three Well Fields Southwest Portion of the Naval Weapons Industrial Reserve Plant, Bethpage, New York Analysis of Factors Affecting Plume Remediation in a  Sole-Source Aquifer System, Nassau County, New York (Northrup Grumman Plume) Hydrogeology of the Virgil Creek Valley in the Town of Dryden, Tompkins County, New York Determination of Sources of Water to the Tully Valley Mudboils 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 Geohydrology and Water Quality of the Northern and Central Parts of the Tug Hill Glacial Aquifer, Jefferson and Oswego Counties, North Central New York Hydrogeology of Two Areas of the Tug Hill Glacial-drift Aquifer, Oswego County, New York The Use of Solute-transport Methods to Estimate Time-varying Nitrogen Loading Rates to the Peconic Estuary Resulting from Wastewater and Fertilizer Inputs to Groundwater in Suffolk County, New York (Peconic Solute Transport) 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 Aquifer texture data describing the Long Island aquifer system Ground-water-flow model of the Shenandoah Valley, Virginia and West Virginia Simulation of Contributing Areas to Selected Public Water-Supply Wellfields in the Valley-Fill Aquifers of New York State Groundwater Availability of the Northern Atlantic Coastal Plain