This USGS data release contains (1) geologic-unit top-surface altitudes in boreholes and (2) aquifer-test time-series water-level drawdowns, recoveries, and supporting data from the Piney Point aquifer in Virginia from 2009 through 2015. Extents, compositions, configurations, and geologic relations of six geologic units that compose the Piney Point aquifer were determined from geologists’ logs of sediment core and cuttings, borehole geophysical logs, and drillers’ logs. The Piney Point aquifer is characterized to address information needs for water-resource management in the Virginia Coastal Plain. Information on the Piney Point aquifer can benefit water-resource management in siting production wells, predicting likely well yield, and anticipating water-level response to withdrawals.

A hydrogeologic framework was developed by USGS during 2016-19 to describe the groundwater system on the Virginia Eastern Shore. This USGS data release contains text files of (1) interpreted borehole hydrogeologic-unit top-surface altitudes, (2) summary values of previously documented estimates of aquifer hydraulic properties, and (3) groundwater-sample chloride concentrations and well summary statistics. In addition are shapefiles of altitude contours for 10 hydrogeologic-unit top surfaces, and for the groundwater 250 milligrams per liter chloride-concentration surface. This data release supports the following publication: McFarland, E.R., and Beach, T.A., 2019, Hydrogeologic framework of the Virginia Eastern Shore: U.S. Geological Survey Scientific Investigations Report 2019-5093, 26 p., 13 pl., https://doi.org/10.3133/sir20195093.

This dataset contains 10-foot contours of the 2013 Piney Point aquifer potentiometric surface in the Coastal Plain of New Jersey. The potentiometric-surface contours show altitudes at which water levels would have risen in tightly-cased wells and represent conditions in October 2013 through January 2014. Groundwater-level data from 56 wells cased in, and with the screened interval open to the Piney Point aquifer, were used to construct the potentiometric surface and are publicly available from the U.S. Geological Survey's National Water Information System.

Point data pp1773_unit_alt_boreholes represent the 309 locations of various types of boreholes that were used to determine the altitudes of each of the 16 hydrogeologic unit layers, plus the land surface altitude at the point location. The layers were used in the regional groundwater availability study of the aquifer system described in Professional Paper 1773, Groundwater Availability in the Atlantic Coastal Plain of North and South Carolina. Each layer is referred to as its model layer number as represented in the report PP1773. For clarity, they are listed below along with the aquifer unit or confining unit name in North Carolina and correlated name in South Carolina. L1 Surficial aquifer L2 Yorktown confining unit / Upper Floridan confining unit L3 Yorktown aquifer / Upper Floridan aquifer L4 Castle Hayne - Pungo River confining unit / Middle Floridan confining unit (To be referred to as "Castle Hayne / Middle Floridan confining unit" in this document) L5 Castle Hayne - Pungo River aquifer / Middle Floridan aquifer (To be referred to as "Castle Hayne - Middle Floridan aquifer" in this document) L6 Beaufort confining unit / Gordon confining unit L7 Beaufort aquifer / Gordon aquifer L8 Peedee confining unit / Crouch Branch confining unit L9 Peedee aquifer / Crouch Branch aquifer L10 Black Creek confining unit / McQueen Branch confining unit L11 Black Creek aquifer / McQueen Branch aquifer L12 Upper Cape Fear confining unit / Charleston confining unit L13 Upper Cape Fear aquifer / Charleston aquifer L14 Lower Cape Fear confining unit / Gramling confining unit L15 Lower Cape Fear aquifer / Gramling aquifer L16 Lower Cretaceous confining unit and aquifer

The USGS collected water level time series data sets using a submersible pressure transducer at FORGE WELL 58B-32 during an aquifer test from February 12 to February 16, 2024. Transmissivity of the pumped aquifer was estimated to be 37,520-55,080 square feet per day using a Theis solution for unconfined aquifers provided by AQTESOLV software. The hydraulic conductivity of the aquifer was then calculated to be 86-126 feet per day using a saturated aquifer thickness of 436 feet.

This data release contains borehole video and aquifer-test data for the Burnpit well (U.S. Geological Survey [USGS] National Water Information System identification 435240103265301), Mount Rushmore National Memorial, collected in June and July 2020. The data accompany a USGS Scientific Investigations Report by Eldridge and others (2021).

This dataset contains altitudes of selected beds and inferred faults in boreholes within an area of interest determined by the U.S. Environmental Protection Agency (EPA) at the Valmont TCE Superfund site in Luzerne County, Pennsylvania. The selected beds correspond to sections of borehole geophysical logs with elevated natural gamma activity as described in the U.S. Geological Survey (USGS) Open-File Report 2021–1093 (Senior and others, 2021). Geophysical logs were correlated on multiple cross sections in this USGS report, which showed these geologic features and inferred faults in the subsurface. Additionally, thin coal or coaly beds were identified from borehole density logs (Senior and others, 2021). The altitudes of these geologic features where they intersect boreholes as displayed on the cross sections are provided here, as well as locational information for each borehole. Naming conventions used for beds are provided in this dataset only and are not present in Senior and others (2021), thus cross sections from Senior and others (2021) with added labels for bed identifiers are also provided.

Short-term aquifer tests were conducted to estimate hydraulic properties in an alluvial aquifer. Tests included eight single-hole pumping and recovery tests and three slug tests (in a single well). These investigations were conducted in the Wet Mountain Valley, in Custer and Fremont Counties, Colorado. The U.S. Geological Survey (USGS) conducted aquifer tests in May, 2019. These aquifer tests inform the conceptual understanding of the valley-fill aquifer and serve as primary inputs to the numerical groundwater-flow model. Testing was completed in cooperation with the Upper Arkansas Water Conservancy District. This data release contains raw data from aquifer tests, water-level and pumping discharge rate measurements, well logs, graphs of the testing data, and plots of analytical solutions.

In 2006, a cooperative study was established to compile reliable data describing groundwater and surface-water interactions in the Elkhorn and Loup River Basins. The purpose of the study was to address state legislation that requires a sustainable balance between long term water supplies and uses of surface water and groundwater. A groundwater-flow model [hereinafter referred to as the Elkhorn-Loup Model (ELM)] was constructed as part of the first two phases of that study as a tool for understanding the effect of groundwater pumpage on stream base flow and the effects of management strategies on hydrologically connected groundwater and surface-water supplies. The third phase of the study was implemented to gain additional geologic knowledge and update the ELM with enhanced water-budget information and refined discretization of the model grid and stress periods. As part of that effort, the ELM is being reconstructed to include two vertical model layers, whereas phase-one and phase-two simulations (Peterson and others, 2008; Stanton and others, 2010) represented the aquifer system using one vertical model layer. The goal for defining the base of the upper model layer was to divide the model vertically so that the upper layer could have different water transmitting and storage characteristics than the lower layer. Texture descriptions were used in most cases to identify the depth in a test-hole, water-well, or surface-geophysical log at which dividing the aquifer produced contrasting texture characteristics for the upper and lower model layers. The study area covers approximately 30,000 square miles, and extends from the Niobrara River in the north to the Platte River in the south. The western boundary roughly coincides with the western boundary of the Upper Loup NRD, and the eastern boundary roughly coincides with the approximate location of the westernmost extent of glacial till in eastern Nebraska (University of Nebraska, 2005). This data release consists of a point shapefile attributed with values representing the elevation of the base of the upper layer of the two-layer phase-three Elkhorn-Loup Model (ELM) above the vertical datum (National Geodetic Vertical Datum of 1929).

In 2006, a cooperative study was established to compile reliable data describing groundwater and surface-water interactions in the Elkhorn and Loup River Basins. The purpose of the study was to address state legislation that requires a sustainable balance between long term water supplies and uses of surface water and groundwater. A groundwater-flow model [hereinafter referred to as the Elkhorn-Loup Model (ELM)] was constructed as part of the first two phases of that study as a tool for understanding the effect of groundwater pumpage on stream base flow and the effects of management strategies on hydrologically connected groundwater and surface-water supplies. The third phase of the study was implemented to gain additional geologic knowledge and update the ELM with enhanced water-budget information and refined discretization of the model grid and stress periods. As part of that effort, the ELM is being reconstructed to include two vertical model layers, whereas phase-one and phase-two simulations (Peterson and others, 2008; Stanton and others, 2010) represented the aquifer system using one vertical model layer. The goal for defining the base of the upper model layer was to divide the model vertically so that the upper layer could have different water transmitting and storage characteristics than the lower layer. Texture descriptions were used in most cases to identify the depth in a test-hole, water-well, or surface-geophysical log at which dividing the aquifer produced contrasting texture characteristics for the upper and lower model layers. The study area covers approximately 30,000 square miles, and extends from the Niobrara River in the north to the Platte River in the south. The western boundary roughly coincides with the western boundary of the Upper Loup NRD, and the eastern boundary roughly coincides with the approximate location of the westernmost extent of glacial till in eastern Nebraska (University of Nebraska, 2005). This data release consists of a point shapefile attributed with values representing the elevation of the base of the upper layer of the two-layer phase-three Elkhorn-Loup Model (ELM) above the vertical datum (National Geodetic Vertical Datum of 1929).