Earth Sciences Commons^™

Transboundary Groundwater Flow Between Niger And Nigeria In The Iullemeden Aquifer System, Gare Ambrose-Igho

UNLV Theses, Dissertations, Professional Papers, and Capstones

Groundwater is important in regions where water resources are not abundantly distributed such as arid and semi-arid regions. In many countries in Africa, groundwater serves as the most reliable source of water supply and supports over 50% of the African population. Groundwater is stored in underground water-bearing permeable rocks, rock fractures, or unconsolidated materials known as aquifers. Groundwater can be transboundary, meaning it crosses international political boundaries between two or more sovereign states. Transboundary aquifers are prone to overexploitation that depletes the groundwater resource and can cause a lowering of the water table and possible ground subsidence. Overexploitation in transboundary …

Preliminary Geologic Assessment And Pfas Occurrence In Western Cheney, Washington, Sydney Frandsen

2026 Symposium

In 2021 Cheney Water Well #5 was closed due to toxic per- and polyfluoroalkyl substances (PFAS) levels above the current State Action Limits and the National Drinking Water Protection Act (https://www.cityofcheney.org/207/Water), which is a concern since PFAS has been associated to types of cancer, birth defects, and other negative human and environmental health concerns (https://doh.wa.gov/communityand-environment/contaminants/pfas). The City of Cheney also tested two downgradient deep-groundwater-wells (Cheney wells #6 and 7) and halted investigation due to the wells being below state and federal drinking water standards. However, a local resident’s shallow groundwater well tested to be above federal and state levels of …

Groundwater Responses To Tidal Restoration At Pelican Marsh And Sea-Level Rise In Elkhorn Slough, California, Julie E. Nelson

Graduate Theses and Dissertations

Coastal wetlands represent a dynamic but vulnerable terrestrial-aquatic interface with future resilience controlled by historic hydrologic alterations, sea-level rise, and groundwater extraction. In diked coastal settings, poor tidal connectivity can degrade habitat from the impoundment of freshwater or hypersaline surface waters. Restoring tidal connectivity could foster marsh revitalization, but altering the surface hydrologic system could lead to unwanted salinity intrusion in shallow aquifers. Saline groundwater intrusion degrades freshwater quality and, while inevitable with sea-level rise, could be accelerated with tidal marsh restoration. To investigate this, I developed a steady-state groundwater flow model of Pelican Marsh, a diked, muted tidal marsh …

Using Geoscience To Empower A Community And Provide Access To Potable Groundwater, Hendratta Ali Dr

SACAD: Scholarly Activities

Access to potable water remains challenging around the world and remains one of the UN Sustainable Development Goals for 2030. Barriers to clean water access are exacerbated by the lack of technical expertise, limited funding for education and training, and the absence of reliable infrastructure that provides access to clean water. The Geoscientists Without Borders program, supported FHSU with funding to test, explore and provide access to clean potable groundwater to a rural community in Cameroon. We conducted water quality analyses, identified, mapped and located deep aquifers in fractured metamorphic rocks. Water quality analyses showed acidic pH and elevated amounts …

A Geospatial Assessment Of Groundwater Salinization In A Multi-Aquifer System: Durango, Mexico, Juan Lopez-Sierra

Graduate Theses/Dissertations

Groundwater salinization poses a critical environmental concern for water resource sustainability in arid and semi-arid regions. This study evaluates spatial and temporal patterns of groundwater salinity across the state of Durango, Mexico, using total dissolved solids (TDS), sodium adsorption ratio (SAR), as salinity indicators and nitrate-nitrogen (NO₃–N) as an anthropogenic indicator. Groundwater quality data were obtained from (CONAGUA), a Mexican water agency. To assess salinity variations with respect to time, while minimizing interannual sampling bias, two multi-year sampling periods were selected: 2012-2013, and 2020-2021. Final datasets consisted of 122 wells for 2012–2013 and 131 wells for 2020–2021. The wells were …

Nebraska Statewide Groundwater-Level Monitoring Report 2025, Aaron R. Young, Mark E. Burbach, Sue Olafsen Lackey, Robert Matthew Joeckel, Jeffrey Westrop

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.

Characterizing A Low-Gradient Stream In Central Illinois As Gaining Or Losing And Observing Seasonal Changes In This Behavior, Eric Timothy Brunner

Theses and Dissertations

While the seasonal behaviors of low-gradient streams have been studied, the behavior of surface water and groundwater interactions within low-gradient streams in glaciated terrain is not fully understood. A third order, low-gradient glacial stream with a saturated riparian buffer in central Illinois was studied to determine the direction of flow between the surface water and groundwater. The goals of this study were to determine 1) whether the stream was gaining or losing water, and 2) whether the gaining or losing nature of the stream-aquifer system changes seasonally. At both an upgradient and downgradient location, two wells were installed: one in …

Bridging The Gap: Evaluating Gnss-Derived Total Water Storage As A Groundwater Monitoring Tool In The Colorado River Basin, Michelle Lee Barton

Graduate Student Theses, Dissertations, & Professional Papers

Groundwater resources in the Colorado River Basin are critically stressed yet remain under-monitored and under-regulated, creating urgent need for reliable, continuous observations at multiple spatial scales. This study evaluates the performance of the University of Montana Global Navigation Satellite Systems (GNSS) terrestrial water storage dataset as a tool for bridging groundwater monitoring gaps across the Upper and Lower Colorado River Basins between 2006 and 2024. We compare GNSS-derived total water storage and groundwater storage estimates against NASA’s Gravity Recovery and Climate Experiment (GRACE) satellite observations and in-situ groundwater well measurements at regional and sub-regional scales. We employ a Bayesian autoregressive …

No Groundwater, No Fish: The Critical Role Of Groundwater In Supporting Non-Glacial, Salmon-Bearing Rivers In South-Central Alaska, Tyelyn Brigino, Kai Rains, Edgar Guerron-Orejuela, Jacob Argueta, Syverine Bentz, Coowe Walker, Mark Rains

School of Geosciences Faculty and Staff Publications

Groundwater discharge plays an important role in the hydrologic and ecologic functioning of rivers including sustaining streamflow and related habitat year-round. Simultaneously, groundwater supports the increasing demands of people as the global population continues to grow. Balancing the needs of users becomes increasingly important as climate change introduces greater uncertainty in water resources and fisheries, especially for economically important anadromous species that depend on freshwater resources. We investigated the seasonal and regional variability of groundwater contributions to six non-glacial mainstem salmon-bearing rivers in south-central Alaska. We hypothesized that groundwater contributes more than half of the annual streamflow, and nearly all …

Multi-Scale Insar Investigations Of Anthropogenic And Natural Processes In The American Southwest, Emily Jo Graves

Geosciences

Arid regions in the American Southwest undergo measurable surface deformation driven by variations in subsurface fluid pressure, and other natural and anthropogenic processes. These processes range from regional scale aquifer dynamics to local oil and gas wellsite activities. This dissertation produces and then utilizes InSAR-derived average velocity fields and displacement time series to reveal and understand these multi-scale processes, their interactions, and impacts for a portion of the American Southwest. Chapter 1 discusses the climate and natural and anthropogenic processes present in our study area. In Chapter 2, we generate detailed large scale average velocity maps that reveal deformation associated …

Groundwater Arsenic Contamination In The Oro Grande Wash, Dalila Boice

Electronic Theses, Projects, and Dissertations

This study investigates the distribution of naturally occurring arsenic in groundwater within the Oro Grande Wash in San Bernardino County, California. Depth-discrete groundwater quality data were collected over multiple years using nested and Westbay monitoring wells. Water quality results showed higher levels of arsenic in the deeper aquifers, ranging between 600 feet and 1,000 feet below ground surface. Arsenic levels in these regions reached as high as 66 µg/L. At roughly 800 feet and below, water quality data from the wells reveal that arsenic concentrations exceeded the 10 µg/L maximum contaminant level (MCL) in 87% of cases. These data provide …

Final Draft Report - Mapping Pfas In Groundwater Of The West Plains, Spokane County, Washington, 2023-2025, Chad Pritchard

EWU PFAS Research Collection

Since 2017, per- and polyfluoroalkyl substances (PFAS) have been detected in West Plains groundwater. Sampling conducted by Fairchild Air Force Base (FAFB) and the Environmental Protection Agency (EPA) have measured PFAS concentrations in private wells that exceed drinking water standards. Two known sources of PFAS have been identified on the West Plains: FAFB and Spokane International Airport (SIA). Washington Department of Ecology (Ecology) awarded the City of Medical Lake an area-wide groundwater grant to develop a groundwater model of PFAS contamination in the West Plains, the grant was originally written by Eastern Washington University (EWU) and Spokane County Water Resources …

Dream Pilot Project: Analysis Of Groundwater Development At Six Villages In Ethiopia, Lindsay K. Gordon

All Graduate Reports and Creative Projects, Fall 2023 to Present

This study presents a hydrogeologic assessment of the Distributed Renewable Energy Agriculture Modalities (DREAM) pilot project, an ongoing groundwater development initiative in rural Ethiopia. This project integrates solar-powered groundwater infrastructure across six villages to improve water access, agricultural productivity, and economic stability.

Fourteen production wells were installed at Murche, four at Dalle, and additional test wells at Murche, Dalle, Chefe Kora, and Huluku. Transmissivity values and the number of wells at Murche suggest that local water needs are currently being met. In contrast, fewer wells were drilled at Dalle. This reflects the high cost of well construction relative to yield, …

Groundwater In Nebraska, Troy E. Gilmore, Jesse T. Korus Dr.

Conservation and Survey Division: Faculty and Staff Publications

What is groundwater? Groundwater is water that fills and moves between spaces in underground rocks, gravel, sand, or other materials.

Using Radium Isotopes To Compare Nutrient Inputs Via Submarine Groundwater Discharge To Offshore Export On The West Florida Shelf, Andrew L. Lindgren

OES Theses and Dissertations

Radium isotopes have been used to trace submarine groundwater discharge (SGD) and associated nutrient and metal inputs into the coastal ocean. They have also been used to estimate rates of diffusive mixing and export fluxes of dissolved constituents offshore. However, use of both approaches in tandem to determine the fate of groundwater inputs after they enter the coastal ocean is still relatively unexplored. Radium isotopes and nutrients were measured in two cross-shelf cruises on the West Florida Shelf in different seasons and in quarterly sampling of offshore wells. Through 226Ra mass balance and 223Ra-derived diffusive mixing rates, inputs of nutrients …

Older Groundwater Reservoirs In Nebraska, Marvin P. Carlson, Steven S. Sibray

Conservation and Survey Division: Faculty and Staff Publications

Sedimentary rocks below Nebraska's regional water table are saturated down to the crystalline igneous and metamorphic rocks of Precambrian age. The total thickness of these sedimentary rocks ranges from about 600 feet to over 10,000 feet. Nearly all current wells in Nebraska produce water from the near-surface, unconsolidated or partly consolidated rocks. Most studies to date -- interpretive reports, test drilling, inventory of wells, monitoring water levels, and water quality determinations -- have concentrated on these near-surface sources of groundwater.

Quaternary Subsurface Characterization Of The Mississippi River Valley Alluvial Aquifer: Insights From Interval Kriging And Airborne Em-Borehole Data Integration, Yuqi Song

LSU Doctoral Dissertations

The Pleistocene period significantly contributed to the formation of alluvial aquifer worldwide. These productive aquifers are crucial for domestic, industrial, and agricultural water supplies. The Mississippi River Valley alluvial aquifer (MRVA), a principal aquifer in the U.S., is crucial for national food security and global agricultural supply. This study aims to characterize the subsurface architecture of the MRVA, thereby enhancing fundamental understanding of sedimentological processes involved in the genesis of glacio-fluvial aquifers worldwide. The research objectives are threefold: (1) to provide a detailed characterization of the MRVA; (2) to develop 3D geostatistical methods for geological modeling; and (3) to develop …

Impact Of Carbonate-Hosted Zn-Pb Ore Deposits On Groundwater Chemistry: Üzümcü-Olgunlar Mining Site (Hakkari, Türkiye), Ci̇han Tuncer, Yüksel Örgün Tutay, Muhterem Demiruğlu

Turkish Journal of Earth Sciences

Hakkari, known for its high economic value Zn-Pb deposits in Türkiye, has been predominantly producing Zn ore for about 20 years. This study investigated the hydrogeochemical properties of groundwater and surface water collected from the vicinity of carbonate-oxide Zn-Pb mine sites in southern Hakkari to evaluate the effects of mineral deposits and mining activities on groundwater chemistry, as there are potential sources of natural pollution. Samples were collected four times at regular intervals during 2021–2022 from points determined upstream, downstream, and around the mine sites, springs, and streams. The samples were analyzed for majorions, trace elements, and isotopes (18O, 2H, …

A Key Technology For Synergistic Backfilling Of Coal-Based Solid Waste And High-Salinity Wastewater, Dong Shuning, Yu Shujiang, Dong Xingling, Zhang Buqin, Guo Xiaoming, Wang Xiaodong, Wang Kai, Zhu Shibin, Wu Boqiang, Liu Lei

Coal Geology & Exploration

Background and Objective Limited by locations, as well as economic and technical levels, most of the coal-based solid waste is still accumulated in the form of open-air landfills without treatment, thus occupying large quantities of land resources and causing secondary pollution to the environment. The proper treatment and reduction of high-salinity wastewater (e.g., high-salinity mine water and high-salinity water from the coal chemical industry) represent a key link in the achievement of zero liquid discharge. However, existing technologies for high-salinity wastewater treatment are generally confronted with issues such as great initial investment and high operation costs of the treatment engineering. …

Geospatial Machine Learning Approaches For Studying Urbanization Impact, Surface Reflectance Patterns, And Groundwater Health Risks, Bibhash Nath

Theses and Dissertations

Geospatial machine learning techniques have been used to study: the impact of urbanization on land use and land cover change, surface reflectance patterns in boreal regions, and groundwater health risks from arsenic in India. These studies combined spatial data, remote sensing, and predictive models to gain valuable insights for sustainable living and protecting human health.

Water Quality And Microplastic Contamination In An Urbanizing City Nakhon Pathom, Thailand, Boonyarak Chuanchit

Graduate Research Theses & Dissertations

Microplastics (MPs) are synthetic polymer particles less than 5 mm in size that originate from both primary manufacturing and the breakdown of larger plastics. Extensive studies have examined their occurrence in other environments, while little is known about their presence and behavior in groundwater, especially in urbanizing regions in Southeast Asia. This study investigates the occurrence and abundance of microplastics within groundwater systems of Nakhon Pathom, an urbanizing province in central Thailand.

Groundwater was collected representing shallow and deep aquifers between May 2023 and May 2025. The analyses included physical-chemical parameters, major ions, heavy metals, and microplastic abundance and composition. …

Assessing Potential For Managed Aquifer Recharge On The Manastash Alluvial Fan: A Geochemical Analysis, Elif A. Myers

All Master's Theses

In south-central Washington, the Yakima River Basin spans 6,100 square miles, encompassing approximately 10% of the state. With a growing population and over 400,000 acres of irrigated cropland, reliable water availability is vital for supporting agricultural irrigation, municipal needs, and aquatic habitats. To ensure water for future use, Managed Aquifer Recharge (MAR), the practice of applying surface water to aquifers for storage or hydrologic system benefit, has been proposed within the Yakima Basin Integrated Plan (YBIP). This research explores the Manastash alluvial fan–located west of Ellensburg, Washington as a potential region for two MAR methods: Shallow Aquifer Recharge (SAR) and …

Origins And Mechanisms Of Mobility Of Geogenic Arsenic Contamination In Toutle And Silver Lake, Wa, Usa, William A. Hays

All Master's Theses

Arsenic (As), a common contaminant in groundwater, is toxic to human health and has a maximum contaminant level of 10 ppb set by both the World Health Organization and the U.S. Environmental Protection Agency (ATSDR, 2007). In Toutle, WA, USA (30 km west of Mount Saint Helens), a private well, labelled TOU1, was previously identified with ~670 ppb of As and was the impetus of this study. This study targeted private wells in the vicinity of TOU1 to identify the extent of the arsenic contamination, identify the aquifer(s) of concern, and identify the mechanism(s) of mobility.

The wells were screened …

Sulfate Sources In Groundwater From An Agricultural Area Central Illinois, Christabel I. Obi

Theses and Dissertations

Increasing sulfate (SO₄^2-) concentrations in the water environment, corresponding with increases in urbanization and industrialization, are a rising global concern. Over 250 mg/L, sulfate threatens human health and ecosystems. Elevated concentrations influence carbonate rock weathering, contributing to the evolution of the global carbon cycle. Knowledge of sulfate sources, whether natural or anthropogenic, is essential for understanding sulfate transport and fate in groundwater. This study investigates SO₄^2- origin and transport in groundwater in an area dominated by agricultural land use in Mclean County, Illinois. Specifically, we explored these questions: 1) Do sulfate concentrations change with groundwater …

Investigating Heterogeneity Of Hydraulic Conductivity And Its Influence On Groundwater Flow Dynamics Within A Saturated Riparian Buffer In Central Illinois, Joseph L. Awuku

Theses and Dissertations

The use of Saturated Riparian Buffers (SRBs) in agricultural settings as a means of reducing contamination of surface water and groundwater resources has gained popularity due to their trapping ability and solute removal (nutrient recycling) capacity. In light of SRB’s nutrient-trapping and removal ability, numerous studies have been conducted to characterize the effectiveness of SRBs. However, most studies on SRBs have paid minimal attention to heterogeneity of hydraulic conductivity (K) and groundwater flow dynamics within SRBs. This study investigated the heterogeneity in horizontal K and estimated the vertical groundwater-specific discharge (q_v) between the upper weathered and its …

Changes In Efficiency And Magnitude Of Recharge Due To Climate Change For Headwater Catchments In The Mountain West, Harrison Mcgillen

Graduate Student Theses, Dissertations, & Professional Papers

Changes to groundwater recharge and stream flow were simulated from downscaled CMIP6 global climate models in a headwater catchment of the Blackfoot River, MT. A calibrated, 3-D, coupled surface and groundwater GSFLOW model, forced with minimum and maximum temperature, and precipitation from a downscaled CMIP6 simulation was used to quantify groundwater recharge and stream flow. The model was calibrated against measured groundwater head and stream flow using observed temperature and precipitation boundary conditions. The calibrated model was then forced with downscaled temperature and precipitation from the CANESM5 model for the SSP245, 370 and 585 scenarios, as well as a manual …

Radon And Radium Isotope Signatures On A Massive Ice- And Permafrost-Rich Coastline, Lauren Kipp, Gwénaëlle Chaillou, Markus Kienast, Joseph Tamborski, Dustin Whalen

OES Faculty Publications

Rapid warming in the Arctic is degrading permafrost and massive ice deposits, which releases solutes previously trapped in ice and frozen soils into groundwater, rivers, and the coastal ocean. Radium and radon isotopes are enriched in groundwaters and may therefore have utility as tracers for the delivery of permafrost-derived solutes to the ocean, particularly if massive ice- or permafrost-derived meltwaters have a distinct isotopic ratio. The ratio of radium isotopes within massive ice deposits can also be used to constrain timescales of ice segregation, as the four isotopes will decay with known rates once removed from contact with sediments. Here …

Unveiling Hidden Mercury And Methylmercury Sources: The Role Of Submarine Groundwater Discharge In Coastal Lagoons, Céline Lavergne, Júlia Rodriguez-Puig, Clara Ruiz-González, Maria Montero-Curiel, Gemma Casas, Daniel Romano-Gude, Irene Alorda-Montiel, Júlia Dordal-Soriano, Aaron Alorda-Kleinglass, Marc Diego-Feliu, Javier Gilabert, Alex Campillo-De La Maza, Cristina Romera-Castillo, Natalia Torres-Rodriguez, Lars-Eric Heimbürger-Boavida, Jordi Garcia-Orellana, Valenti Rodellas, Andrea G. Bravo

OES Faculty Publications

Mercury loads from Submarine Groundwater Discharge (SGD) may represent an overlooked source of methylmercury (MeHg) to the ocean, affecting human and ecosystem health. The SGD process involves the flow of fresh, saline, or mixed groundwater from coastal aquifers into the oceans classified in different components. Existing studies rarely report the fluxes supplied by the different SGD components; therefore, the relevance of SGD as a source of mercury remains unclear. We aimed to quantify SGD-driven mercury/methylmercury fluxes to the coast, focusing on the largest coastal lagoon in the western Mediterranean. We measured total dissolved mercury and MeHg in surficial and porewaters …

Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise

Cal Poly Humboldt theses and projects

This study addresses the significant concern of stream depletion from groundwater pumping in Humboldt County, CA. The objective of this study is to develop an analytical model for estimating stream depletion and integrating field data into model parameters.

The methodology involved conducting a field study near three operating wells by a stream, installing stream gages upstream and downstream of the wells, and recording pumping rates and schedules for two of the wells. The third well’s pumping data was synthetically generated, for privacy concerns of the well owner. The StreamDepletR package was used for estimating depletion rates in a stream in …

Pumping Groundwater For Salinity Control In Wa, Department Of Primary Industries And Regional Development, Western Australia

Natural resources factsheets

DPIRD recommends that groundwater pumping is used as part of an integrated water and salinity management program.

Groundwater pumping can lower local water tables, recover land for production and reduce the spread of local salinity or to protect high value assets at risk, such as townsites, roads or railway lines. Pump water can be discharged to safe disposal points or used on farm for desalination.