Publications

Water-quality data collected from 1,426 wells during 1993-2003 as part of the U.S. Geological Survey National Water-Quality Assessment (NAWQA) program were evaluated to characterize the water quality in glacial and bedrock aquifers of the northern United States. One of the goals of the NAWQA program is to synthesize data from individual studies across the United States to gain regional- and nation

Digital terrain models, which can be produced from multibeam bathymetric data, are ordered arrays of depths for a number of sea-floor positions sampled at regularly spaced intervals. These models provide valuable base maps for marine geological interpretations that help define the variability of the sea floor (one of the primary controls of benthic habitat diversity), improve our understanding of

This report presents the results of a study by the U.S. Geological Survey (USGS), in cooperation with the Chester County Water Resources Authority (CCWRA), to update the drought-trigger water levels for the Chester County observation-well network. The Chester County observation-well network was established in 1973 through a cooperative agreement between the CCWRA and the USGS to monitor local grou

Visitors to Shenandoah National Park (SNP) enjoy the animal and plant life and the scenery but may not realize how vulnerable these features are to various threats, such as invasion of exotic plants and insects, improper use of park resources by humans, and air and water pollution. The National Park Service strives to protect natural resources from such threats to ensure that the resources will be

Most of the northern half of Warren County is in the Northwestern Glaciated Plateau Section of the Appalachian Plateaus Physiographic Province. The remainder of the county is in the High Plateau Section. The glacial outwash sand and gravel hydrogeologic unit is the most extensively used unconsolidated unit for water supply in Warren County because it is capable of yielding large amounts of water t

The U.S. Geological Survey (USGS), U.S. Environmental Protection Agency (USEPA), Chesapeake Bay Program (CBP), Interstate Commission for the Potomac River Basin (ICPRB), Maryland Department of the Environment (MDE), Virginia Department of Conservation and Recreation (VADCR), and University of Maryland (UMD) are collaborating to improve the resolution of the Chesapeake Bay Regional Watershed Model

This investigation is the first regionally focused study of the presence of natural radioactivity in water from the Vincentown and Wenonah-Mount Laurel aquifers, Englishtown aquifer system, and the Hornerstown and Red Bank Sands. Geologic materials composing the Vincentown and Wenonah-Mount Laurel aquifers and the Hornerstown and Red Bank Sands previously have been reported to contain radioactive

Mill Creek in Cleveland, Ohio, receives discharges from combined-sewer overflows (CSOs) and other sanitary-sewage inputs. These discharges affect the water quality of the creek and that of its receiving stream, the Cuyahoga River. In an effort to mitigate this problem, the Northeast Ohio Regional Sewer District implemented a project to eliminate or control (by reducing the number of overflows) all

The U.S. Geological Survey (USGS) is working with the National Oceanic and Atmospheric Administration (NOAA) to interpret the surficial geology in estuaries and sounds along the northeastern coast of the United States. This report interprets the area covered by NOAA Survey H11320, about 72 km² of sea floor in eastern Rhode Island Sound (RIS), located about 8 km south of Sakonnet Point, Rhode Islan

A ground-water flow model previously developed as part of a Regional Aquifer System Analysis (RASA) of the New Jersey Coastal Plain was used to simulate ground-water flow in eight major confined aquifers to help evaluate ground-water resources in support of the New Jersey Department of Environmental Protection's revision of the New Jersey State Water Supply Plan. This model was calibrated to 1998

The purpose of the Reston Stable Isotope Laboratory (RSIL) lab code 2899 is to determine the δ15N of nitrate (NO3-) in water. The δ15N of the dissolved NO3- is analyzed by conversion of the NO3- to nitrous oxide (N2O), which serves as the analyte for mass spectrometry. A culture of denitrifying bacteria is used in the enzymatic conversion of the NO3- to N2O, which follows the pathway shown in equa

Time-series photographs of the sea floor were obtained from an instrumented tripod deployed in western Massachusetts Bay at LT-A (42° 22.6' N, 70° 47.0' W; nominal water depth of 32 m; fig. 1) from December 1989 through September 2005. The photographs provide time-series observations of physical changes of the sea floor, near-bottom water turbidity, and life on the sea floor. Several reports prese