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Groundwater

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Full-Text Articles in Physical Sciences and Mathematics

Nebraska Groundwater In Storage, Conservation Survey Division Jan 9999

Nebraska Groundwater In Storage, Conservation Survey Division

Conservation and Survey Division

No abstract provided.


Groundwater Regions In Nebraska Jan 9999

Groundwater Regions In Nebraska

Conservation and Survey Division

No abstract provided.


Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed May 2019

Potential Contamination Risk In Tennessee Aquifers From Oil And Gas Drilling, Emma Reed

University of Tennessee Honors Thesis Projects

No abstract provided.


Assessing Dissolved Methane And Halogen Patterns In Groundwater Of New York State, Shannon Garvin Aug 2018

Assessing Dissolved Methane And Halogen Patterns In Groundwater Of New York State, Shannon Garvin

Theses - ALL

Due to the ban on hydraulic fracturing for natural gas in New York State (NYS), it serves as an ideal location to study the natural processes that control the migration of dissolved methane and high salinity fluids found at depth. The hydrogeologic setting of NYS is analogous to that of Northern Pennsylvania where unconventional exploration has not been restricted. Halogens geochemically behave conservatively and can be found in unique proportions. Therefore, they serve as useful tracers for the natural movement of groundwater. The focus of our study is to: 1) establish a more cohesive baseline for groundwater quality data for ...


Estimating The Permanent Loss Of Groundwater Storage In The Southern San Joaquin Valley, California, Ryan G. Smith, Rosemary Knight, J. Chen, J. A. Reeves, H. A. Zebker, T. Farr, Z. Liu Aug 2018

Estimating The Permanent Loss Of Groundwater Storage In The Southern San Joaquin Valley, California, Ryan G. Smith, Rosemary Knight, J. Chen, J. A. Reeves, H. A. Zebker, T. Farr, Z. Liu

Ryan G. Smith

In the San Joaquin Valley, California, recent droughts starting in 2007 have increased the pumping of groundwater, leading to widespread subsidence. In the southern portion of the San Joaquin Valley, vertical subsidence as high as 85 cm has been observed between June 2007 and December 2010 using Interferometric Synthetic Aperture Radar (InSAR). This study seeks to map regions where inelastic (not recoverable) deformation occurred during the study period, resulting in permanent compaction and loss of groundwater storage. We estimated the amount of permanent compaction by incorporating multiple data sets: the total deformation derived from InSAR, estimated skeletal-specific storage and hydraulic ...


Overpumping Leads To California Groundwater Arsenic Threat, Ryan G. Smith, Rosemary Knight, Scott Fendorf Aug 2018

Overpumping Leads To California Groundwater Arsenic Threat, Ryan G. Smith, Rosemary Knight, Scott Fendorf

Ryan G. Smith

Water resources are being challenged to meet domestic, agricultural, and industrial needs. To complement finite surface water supplies that are being stressed by changes in precipitation and increased demand, groundwater is increasingly being used. Sustaining groundwater use requires considering both water quantity and quality. A unique challenge for groundwater use, as compared with surface water, is the presence of naturally occurring contaminants within aquifer sediments, which can enter the water supply. Here we find that recent groundwater pumping, observed through land subsidence, results in an increase in aquifer arsenic concentrations in the San Joaquin Valley of California. By comparison, historic ...


Hardbottom Characterization And Relationship To The Geologic Framework In Long Bay, South Carolina, Cathryn J. Wheaton Jul 2018

Hardbottom Characterization And Relationship To The Geologic Framework In Long Bay, South Carolina, Cathryn J. Wheaton

Electronic Theses and Dissertations

Hardbottom seafloor is a common element among sediment-starved portions of the inner continental shelf along the U.S. Atlantic margin. These areas are characterized by indurated sediment surfaces that are heavily altered by biological and physical processes. Long Bay, in northeastern South Carolina, offers ideal environmental conditions for hardbottom exposure with only patchy Holocene sand deposits, interspersed with extensive hardbottom areas. Here we use high-resolution multibeam bathymetry, CHIRP subbottom profiling and electrical resistivity data, along with surficial sediment samples, hardbottom thin sections, and water column radioisotope (radon-222) analysis to investigate the origin and geologic framework of a region of hardbottom ...


Tree Ring Disturbance Clustering For The Collapse Of Long Tree-Ring Chronologies, John Woodmorappe Jul 2018

Tree Ring Disturbance Clustering For The Collapse Of Long Tree-Ring Chronologies, John Woodmorappe

The Proceedings of the International Conference on Creationism

The Disturbance-Clustering hypothesis, first introduced here, posits that geographically-demarcated subtly-perturbed tree rings had induced the affected trees to crossmatch not in accordance with climatic signals, as is assumed in conventional dendrochronology. They instead crossmatch only within a geographic cluster of like-perturbed trees, and not with those of other clusters or with any of the remaining unaffected climatically-governed trees. During chronology-building, these clusters became connected with each other, into an artificially-long chronology, by means of rarely-occurring fortuitously-crossmatching “bridge” series. An experiment involving fifteen ostensibly heterochronous ancient trees graphically supports this hypothesis. Merely one-per-decade individual-ring perturbations induce all fifteen series to form ...


Using Regression Analysis To Determine Land Cover Impacts On Groundwater Levels In The High Plains, Dylan T. Riley Jul 2018

Using Regression Analysis To Determine Land Cover Impacts On Groundwater Levels In The High Plains, Dylan T. Riley

Dissertations and Theses in Agricultural Economics

Many parts of the High Plains region are facing declining aquifer levels, which threatens the long-term viability of irrigated agriculture. Furthermore, some areas of the High Plains region, like the Republican River Basin in Nebraska, need to keep groundwater levels high enough in the short-term to ensure that hydrologically connected rivers have enough streamflow to fulfill surface water obligations, such as Nebraska's interstate river compact with Colorado and Kansas. To better manage groundwater, it is important to understand the unintended effects of policies that may not be aimed at groundwater conservation, such as the USDA- Conservation Reserve Program (USDA-CRP ...


Estimating Adaptation To Climate Change In Groundwater Irrigation, James Keeler Jul 2018

Estimating Adaptation To Climate Change In Groundwater Irrigation, James Keeler

Dissertations and Theses in Agricultural Economics

Understanding the adaptive capacity of irrigated agriculture, including to what extent producers adjust irrigation choices along the intensive and extensive margins, is vital to the development of accurate and holistic estimates of the impacts of climate change on agricultural production and the sustainability of water-related ecosystem services. This thesis proposes and implements a natural experiment using statistical matching methods to estimate how producers adjust groundwater extraction, irrigated crop acreage, and irrigation technology in response to long-term changes in precipitation and evapotranspiration. Results from groundwater irrigated fields in Kansas suggest that intensive and extensive margin water use adaptations are generally limited ...


Numerical Modeling Of The Effects Of Land Use Change And Irrigation On Streamflow Depletion Of Frenchman Creek, Nebraska, Moussa Guira Jul 2018

Numerical Modeling Of The Effects Of Land Use Change And Irrigation On Streamflow Depletion Of Frenchman Creek, Nebraska, Moussa Guira

Dissertations & Theses in Earth and Atmospheric Sciences

A three-dimensional Control Volume Finite Difference-based numerical groundwater flow model was constructed to assess the effects of agricultural irrigation and land use change on streamflow depletion. The study area is Frenchman Creek basin located in southwestern corner of the State of Nebraska, USA. This area was subject to an increased proliferation of groundwater abstraction for agricultural purposes since industrial revolution. It has also been subject to land use change from native rangeland to dry and irrigated cropland. The groundwater flow model was spatially discretized using Voronoi cells in unstructured grid built with the USGS MODFLOW-6. Temporal discretization defined 151 time ...


Isotopic And Geochemical Analysis Of Nitrate Contaminated Groundwater In Edgar, Nebraska, Nathan Roddy Jul 2018

Isotopic And Geochemical Analysis Of Nitrate Contaminated Groundwater In Edgar, Nebraska, Nathan Roddy

Dissertations & Theses in Earth and Atmospheric Sciences

High nitrate concentrations in the groundwater beneath Edgar, Nebraska have been measured for well over a decade, exceeding the EPA’s MCL of 10 mg-N/L. Investigating the isotopic signature of nitrate and groundwater have determined the likely source(s) of contamination. Apparent seasonal changes exists in nitrate concentration, isotope ratios, and geochemistry, suggesting that sources and flow paths change as a result of irrigation. Samples collected in December and May had very similar nitrate concentrations (average value of 13.7 mg-N/L) and isotopic ratios (δ15N 4.46‰ and δ18O-NO3 20.21‰), suggesting synthetic ...


Surface Water And Groundwater In A Changing Climate: Applications Of Hydrogeophysics And Trend Analysis To Understand Hydrologic Systems, Robin Glas Jun 2018

Surface Water And Groundwater In A Changing Climate: Applications Of Hydrogeophysics And Trend Analysis To Understand Hydrologic Systems, Robin Glas

Dissertations - ALL

Water resources are being impacted by anthropogenic climate change worldwide, the nature and severity of that impact is determined by geographic position, local topography, underlying geology, and human influences such as land use, water availability, and water regulation. As global temperatures continue to rise due to greenhouse gas emissions, it is imperative that we better understand how water availability fluctuates with changes in air temperature, rainfall, snowpack, and glacial ice. This dissertation provides an analysis of the hydrologic response to both short-term and long-term climatic changes in both humid-temperate and semi-arid tropical regions. Within the tropical alpine zone, shifts in ...


Column Tests Of Nitrate Breakthrough Behavior In Subsurface Sediments To Understand Transport In The Root-Zone, Rebecca Sally Haworth, Emma Rose Goodwin Jun 2018

Column Tests Of Nitrate Breakthrough Behavior In Subsurface Sediments To Understand Transport In The Root-Zone, Rebecca Sally Haworth, Emma Rose Goodwin

Natural Resources Management and Environmental Sciences

No abstract provided.


Overpumping Leads To California Groundwater Arsenic Threat, Ryan G. Smith, Rosemary Knight, Scott Fendorf Jun 2018

Overpumping Leads To California Groundwater Arsenic Threat, Ryan G. Smith, Rosemary Knight, Scott Fendorf

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Water resources are being challenged to meet domestic, agricultural, and industrial needs. To complement finite surface water supplies that are being stressed by changes in precipitation and increased demand, groundwater is increasingly being used. Sustaining groundwater use requires considering both water quantity and quality. A unique challenge for groundwater use, as compared with surface water, is the presence of naturally occurring contaminants within aquifer sediments, which can enter the water supply. Here we find that recent groundwater pumping, observed through land subsidence, results in an increase in aquifer arsenic concentrations in the San Joaquin Valley of California. By comparison, historic ...


Results Of Test-Hole Drilling For Observation Well Planning In The Lower Loup Natural Resources District, Spring 2017, Douglas R. Hallum P.G., Sue Olafsen Lackey, Steven S. Sibray May 2018

Results Of Test-Hole Drilling For Observation Well Planning In The Lower Loup Natural Resources District, Spring 2017, Douglas R. Hallum P.G., Sue Olafsen Lackey, Steven S. Sibray

Conservation and Survey Division

The High Plains Aquifer underlies much of Nebraska. It is the primary source of groundwater within the Lower Loup Natural Resources District (LLNRD) of central Nebraska. Water derived from the aquifer is an important natural resource for the area and supplies water for recreation, wildlife and agriculture, as well as domestic, municipal, and industrial uses. Falling spring water levels measured in existing observation and irrigation wells have raised concerns about possible changes in water availability, groundwater-surface water relationships and water quality in the area, prompting the LLNRD to propose test holes and the collection of additional groundwater data in the ...


Three Environmental Fluid Dynamics Papers, Eden Furtak-Cole May 2018

Three Environmental Fluid Dynamics Papers, Eden Furtak-Cole

All Graduate Theses and Dissertations

Three papers are presented, applying computational fluid dynamics methods to fluid flows in the geosciences. In the first paper, a numerical method is developed for single phase potential flow in the subsurface. For a class of monotonically advancing flows, the method provides a computational savings as compared to classical methods and can be applied to problems such as forced groundwater recharge. The second paper investigates the shear stress reducing action of an erosion control roughness array. Incompressible Naiver-Stokes simulations are performed for multiple wind angles to understand the changing aerodynamics of individual and grouped roughness elements. In the third paper ...


The Impact Of Land Use On Nitrate-N Movement And Storage In The Vadose Zone Of The Hastings’ Whpa, Craig Adams Apr 2018

The Impact Of Land Use On Nitrate-N Movement And Storage In The Vadose Zone Of The Hastings’ Whpa, Craig Adams

Dissertations & Theses in Natural Resources

Nebraska has one of the largest agricultural economies in the United States and relies heavily on irrigation and fertilizer application to maintain crop yields. Over-irrigation and continuous application of nitrogen (N) in many areas has led to accumulation of nitrate-N in soils and sediments throughout the state’s vadose zone. Because nitrate-N is both persistent and mobile, groundwater concentrations in many areas of Nebraska and other agriculturally intensive states are increasing. Nitrate-N contamination of public and private drinking water supplies that utilize groundwater are of particular concern. Vadose zone sampling is an important method for rapidly assessing the effect of ...


Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler Apr 2018

Hawai'i Wildlife Fund V. County Of Maui, Lowell J. Chandler

Public Land & Resources Law Review

In Hawai’i Wildlife Fund v. County of Maui, the Ninth Circuit held that the plain language of the Clean Water Act provides jurisdiction over indirect discharges of pollutants from a point source into groundwater that is shown to be connected to navigable waters. The court found that studies confirmed pollutants entering the Pacific Ocean were fairly traceable to the County of Maui’s sewage disposal wells. In affirming the district court’s ruling, the Ninth Circuit held that Maui County violated the Clean Water Act by discharging pollutants into a navigable water without the required permit. The court also ...


Groundwater Availability For Summer Low Flows: Co-Production And Shared Application Of Hydrogeologic Tools And Information, Rick Dinicola, Lonna Frans, Wendy Welch Apr 2018

Groundwater Availability For Summer Low Flows: Co-Production And Shared Application Of Hydrogeologic Tools And Information, Rick Dinicola, Lonna Frans, Wendy Welch

Salish Sea Ecosystem Conference

Groundwater discharge to streams and rivers in Puget Sound basin is the primary source of water for sustaining summer low flows and associated aquatic habitat. The science underlying how human and environmental stressors can affect low flows can be difficult for scientists and stakeholders to grasp, largely because it requires understanding the mechanics of groundwater recharge and discharge processes combined with the subtleties of estimating cumulative rates of groundwater extraction and use in subbasins. USGS has initiated a Near-Term Action (NTA) for the 2016 Action Agenda that will better inform our understanding of the effects of current and future stressors ...


Assessing Near Surface Hydrologic Processes And Plant Response Over A 1600 M Mountain Valley Gradient In The Great Basin, Nv, U.S.A., Dale Devitt, Brian Bird, Brad Lyles, Lynn Fenstermaker, Richard Jasoni, Scotty Strachan, Jay Arnone Iii, Franco Biondi, Scott Mensing, Laurel Saito Apr 2018

Assessing Near Surface Hydrologic Processes And Plant Response Over A 1600 M Mountain Valley Gradient In The Great Basin, Nv, U.S.A., Dale Devitt, Brian Bird, Brad Lyles, Lynn Fenstermaker, Richard Jasoni, Scotty Strachan, Jay Arnone Iii, Franco Biondi, Scott Mensing, Laurel Saito

Life Sciences Faculty Publications

This study investigated near surface hydrologic processes and plant response over a 1600 m mountain-valley gradient located in the Great Basin of North America (Nevada, U.S.A.) as part of a long-term climate assessment study. The goal was to assess shifts in precipitation, soil water status and associated drainage with elevation and how this influenced evapotranspiration and plant cover/health estimated by a satellite-derived Normalized Difference Vegetation Index (NDVI), all to better understand how water is partitioned in a mountain valley system. Data were acquired during a three-year period from meteorological stations located in five plant communities ranging in ...


Variation Of Groundwater Divides During Wet And Dry Years In The Wolf River Basin, Northeastern Wisconsin, Susan A. Borchardt Mar 2018

Variation Of Groundwater Divides During Wet And Dry Years In The Wolf River Basin, Northeastern Wisconsin, Susan A. Borchardt

International Journal of Geospatial and Environmental Research

Groundwater divides and surface-water divides do not always coincide, and groundwater divides are not as easy to detect as surface-water divides. Groundwater divides are also dynamic, moving in response to environmental and anthropogenic stresses. This study will investigate how different hydrological stresses can change the size and shape of the study basin and whether the stresses together mitigate or intensify the basin’s response. This study looks at three factors that may affect the size and shape of the Wolf River basin: annual precipitation, soil permeability, and the presence of high-capacity wells. This study examined four groundwater basins that represent ...


Keeping The Clean Water Act Cooperatively Federal—Or, Why The Clean Water Act Does Not Directly Regulate Groundwater Pollution, Damien Schiff Feb 2018

Keeping The Clean Water Act Cooperatively Federal—Or, Why The Clean Water Act Does Not Directly Regulate Groundwater Pollution, Damien Schiff

William & Mary Environmental Law and Policy Review

No abstract provided.


Upstream, Midstream, And Downstream: Dispute System Design For Sustainable Groundwater Management, Janet Martinez, Esther Conrad, Tara Moran Jan 2018

Upstream, Midstream, And Downstream: Dispute System Design For Sustainable Groundwater Management, Janet Martinez, Esther Conrad, Tara Moran

University of St. Thomas Law Journal

No abstract provided.


Estimating Groundwater Inflow And Age Characteristics In An Alluvial Aquifer Along The Little Wind River, Wyoming, Derek Goble Jan 2018

Estimating Groundwater Inflow And Age Characteristics In An Alluvial Aquifer Along The Little Wind River, Wyoming, Derek Goble

Graduate Student Theses, Dissertations, & Professional Papers

We synoptically sampled a 2 km gaining reach of the Little Wind River in central Wyoming for 222Rn, CFCs and SF6 to determine the distributed volumes and locations of discharge and estimate alluvial groundwater age characteristics. 222Rn was sampled in the stream, shallow in-stream piezometers and nearby alluvial groundwater wells to determine the volume and spatial distribution of groundwater discharge to the river. Age tracers, CFC and SF6, sampled in the stream, shallow in-stream piezometers and in alluvial groundwater wells were then used to determine whether in-stream samples are capable of constraining the residence time distribution ...


An Inter-Watershed Comparison Study Of Bedrock Controls On Shallow Subsurface Flow And Streamflow Response, Robert Livesay Jan 2018

An Inter-Watershed Comparison Study Of Bedrock Controls On Shallow Subsurface Flow And Streamflow Response, Robert Livesay

Graduate Student Theses, Dissertations, & Professional Papers

Bedrock controls on watershed response have been actively studied in recent years, however, most conclusions are based on surface water analysis leaving unresolved questions about the nature of bedrock flow paths and ultimately their control on watershed response. In this study, we investigated bedrock controls on watershed response by simultaneously monitoring the hydrology of two adjacent watersheds underlain by dissimilar geologic formations (monzonite vs. meta-sandstone) and by characterizing subsurface conditions through bedrock drilling and fracture mapping. We hypothesized, when soils saturate, the underlying bedrock geology may influence the partitioning of shallow subsurface flow (SSF) between soil and bedrock flow paths ...


Benzene, Toluene, Ethylbenzene, And Xylenes Occurrence In Relation To Oil And Gas Development In The Denver-Julesburg Basin Of Colorado, Mark T. Schroeder Jan 2018

Benzene, Toluene, Ethylbenzene, And Xylenes Occurrence In Relation To Oil And Gas Development In The Denver-Julesburg Basin Of Colorado, Mark T. Schroeder

Civil Engineering Graduate Theses & Dissertations

We quantified the occurrences of benzene, toluene, ethylbenzene, and xylenes (BTEX) in water wells in the Denver-Julesburg Basin and determined the extent to which oil and gas is responsible for contamination. Public environmental sampling records were downloaded with computer scripts between 1988 and 2016 from Colorado Oil and Gas Conservation Commission (COGCC) to find water wells where BTEX compounds were above their detection limits. There were 51 BTEX occurrences in water wells, and for each occurrence, we searched oil and gas wells within a half-mile radius for records on surface casing integrity that could indicate fluid or gas leaks into ...


Using Multiple Environmental Tracers To Investigate The Relative Role Of Soil And Deep Groundwater In Stream Water Generation For A Snow-Dominated Headwater Catchment, Isabellah V. Von Trapp Jan 2018

Using Multiple Environmental Tracers To Investigate The Relative Role Of Soil And Deep Groundwater In Stream Water Generation For A Snow-Dominated Headwater Catchment, Isabellah V. Von Trapp

Graduate Student Theses, Dissertations, & Professional Papers

In this study, seasonal fluctuation of environmental tracers in stream flow, soil water, and deep bedrock groundwater were used to constrain the role of deep bedrock groundwater in streamflow generation for a mountainous headwater catchment. Synoptic measurements of stream discharge, 222Rn, specific conductivity and major ion concentrations were measured throughout the water year over a 5 km reach of Cap Wallace Creek in the Lubrecht Experimental Forest, Montana, U.S.A. with the intention of understanding groundwater – surface water interactions across spatial and temporal scales. Stage measurements were continually recorded at seven stilling well locations along the reach. Discharge ...


Three Essays On The Economics Of U.S. Water Policy, Xianjun Qiu Jan 2018

Three Essays On The Economics Of U.S. Water Policy, Xianjun Qiu

Graduate Theses and Dissertations

The complicated relationship between human activities and water quality/quantity has interested many researchers. My primary research interest lies in environmental economics and water resource policy. This dissertation studies water quality and water quantity in the United States, especially groundwater. In particular, the first chapter, “The Conservation Reserve Program and Nutrient Pollution in Groundwater”, studies how the Conservation Reserve Program (CRP) affects groundwater quality in the United States. The second chapter of my dissertation, “Reliable Drinking Water Supply and Cities’ Resilience to Drought” (joint with Dr. David Keiser, Dr. Gabriel Lade, and Dr. Ivan Rudik), studies how differences in drinking ...


The Groundwater Atlas Of Red Willow County, Nebraska, Dana Divine, Duane Eversoll, Leslie M. Howard Jan 2018

The Groundwater Atlas Of Red Willow County, Nebraska, Dana Divine, Duane Eversoll, Leslie M. Howard

Conservation and Survey Division

The purpose of this groundwater atlas is to synthesize a wealth of hydrogeologic data for Red Willow County that has not been published in readily accessible formats previously. Many of the maps presented here are based on geologic information from registered wells and test holes that is publically available on-line, which becomes more valuable when compiled, analyzed, and discussed as a whole.

In Red Willow County, the aquifers are alluvial sand and gravel in the river and stream valleys and the High Plains aquifer beneath the uplands. The High Plains aquifer in Red Willow County consists primarily of the Ogallala ...