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IntroductionSubmarine groundwater discharge (SGD) is a problem of major proportions on a world-wide scale. The ubiquitous nature of SGD along varied coastlines and its importance to coastal water and geochemical budgets have recently been thrust into the global spotlight . For example, the discharge of nutrient-enriched groundwater into coastal waters...

Pesticides and nutrients move from application areas through ground water and surface runoff to streams on the Delmarva Peninsula. The relative importance of different transport media to the movement of these compounds in different watersheds is related to locally variable hydrologic and geochemical conditions among areas of regionally similar land...

The importance of migration stopover sites in ensuring that migratory birds successfully accomplish their journeys between breeding and non-breeding ranges has come to the forefront of avian research. Migratory birds that breed in western United States (US) and Canada and overwinter primarily in western Mexico migrate across the arid region...

Successful restoration of the southern Florida ecosystem requires extensive knowledge of the physical characteristics and hydrologic processes controlling water flow and transport of constituents through extremely low-gradient freshwater marshes, shallow mangrove-fringed coastal creeks and tidal embayments, and near-shore marine waters. A sound, physically based numerical model can provide simulations of...

A leaking underground gasoline tank contaminated a crystalline bedrock aquifer in Montville, Connecticut, USA with MTBE and benzene. At the original residential bedrock supply wells, the median MTBE concentration was 165 micrograms per liter (mg/L), and the median benzene concentration was 320 mg/L. The maximum concentrations of MTBE and...

Time-lapse monitoring of subsurface processes is an emerging and promising area of hydrogeophysics. The combined use of non-invasive or minimally invasive geophysical methods with hydraulic and geochemical sampling is a cost-effective approach for aquifer characterization, long-term aquifer monitoring, and remediation monitoring. Time-lapse geophysical surveys can indirectly measure time-varying hydrologic parameters...

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Hydrogeology Journal continues to flourish. The increase in the size of our yearly volume attests to the success and growing international reputation of the journal. Until 2001, HJ produced about 600 printed pages each year. This number has steadily increased, and in 2005 and 2006,<i class="EmphasisTypeItalic...

Rates of ground water recharge and discharge are not well known in the central Everglades. Here we report estimates of ground water recharge and discharge at 15 sites in the Everglades Nutrient Removal Project and in Water Conservation Area 2A (WCA-2A), along with measurements of hydraulic properties of peat at...

Effects of aquifer travel time on nitrogen reaction and loading to Popponesset Bay, a eutrophic coastal embayment on western Cape Cod, Massachusetts, are evaluated through hydrologic analysis of flow and transport. Approximately 10% of the total nitrogen load to the embayment is intercepted by fresh water ponds and delivered to...

To complement a large-scale geophysical investigation of occurrence and discharge of fresh water beneath Delaware, Maryland, and Virginia (Delmarva) coastal bays, we measured (1) salinity and nutrient concentrations in ground water samples from several offshore coring sites and (2) a suite of chemical and isotopic parameters, including age tracers, in...

Everglades restoration will alter the hydrology of South Florida, affecting both water depth and salinity levels in the southern fringes of the Everglades, the habitat of the endangered American crocodile (Crocodylus acutus). A key question is what the effects of these hydrologic changes will be on the crocodile population. Reliable...

The 36.1-square-mile Usquepaug–Queen River Basin in south-central Rhode Island is an important water resource. Streamflow records indicate that withdrawals may have diminished flows enough to affect aquatic habitat. Concern over the effect of withdrawals on streamflow and aquatic habitat prompted the development of a Hydrologic Simulation Program–FORTRAN (HSPF) model...

Multiple linear-regression equations were developed to estimate the magnitudes of floods in Connecticut for recurrence intervals ranging from 2 to 500 years. The equations can be used for nonurban, unregulated stream sites in Connecticut with drainage areas ranging from about 2 to 715 square miles. Flood-frequency data and hydrologic characteristics...

Most surface flows to the 20-km-long Maggia Valley in Southern Switzerland are impounded and the valley is being investigated to determine environmental flow requirements. The aim of the investigation is the devel-opment of a modelling framework that simulates the dynamics of...

In many subsurface situations where human health and environmental quality are at risk (e.g., contaminant hydrogeology petroleum extraction, carbon sequestration, etc.),scientists and engineers are being asked by federal agency decision-makers to predict the fate of chemical species under conditions where both reactions and transport are processes of first-order importance.In 2002,...

In 1999, the U.S. Environmental Protection Agency initiated a rule to protect ground water in areas other than source-water protection areas. These other sensitive ground water areas (OSGWAs) are aquifers that are not currently but could eventually be used as a source of drinking water. The OSGWA program specifically addresses...

A hydrologic analysis was made at three canal sites and four tidal sites along the St. Lucie River Estuary in southeastern Florida from 1998 to 2001. The data included for analysis are stage, 15-minute flow, salinity, water temperature, turbidity, and suspended-solids concentration. During the period of record, the estuary experienced...

Historical water-quality samples collected from the Red River over the past 35 years were compiled, reviewed for quality, and evaluated to determine influences on water quality over time. Hydrologic conditions in the Red River were found to have a major effect on water quality. The lowest sulfate concentrations were associated...

This study was designed to characterize the particle-size distribution and the concentrations of total mercury (HgT), methylmercury (MeHg), and other constituents in sediments trapped behind Daguerre Point Dam, a 28-foot-high structure on the lower Yuba River in California. The results of the study will assist other agencies in evaluating potential...

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The Cook Inlet Basin study unit of the U.S. Geological Survey National Water-Quality Assessment Program comprises 39,325 square miles in south-central Alaska. Data were collected at eight fixed sites to provide baseline information in areas where no development has taken place, urbanization or logging have occurred, or the effects of...

A numerical three-dimensional (3D) transient ground-water flow model of the Death Valley region was developed by the U.S. Geological Survey for the U.S. Department of Energy programs at the Nevada Test Site and at Yucca Mountain, Nevada. Decades of study of aspects of the ground-water flow system and previous less...

In cooperation with the U.S. Air Force, the U.S. Geological Survey characterized the ground-water hydrology and water quality at Melrose Air Force Range in east-central New Mexico. The purpose of the study was to provide baseline data to Cannon Air Force Base resource managers to make informed decisions concerning actions...