Physical Sciences and Mathematics Commons^™

Silver Nanoparticle Transport Through Soil: Illuminating The Governing Pore-Scale Processes, Ian L. Molnar

Electronic Thesis and Dissertation Repository

Engineered nanoparticles are widely used and will eventually be released to the subsurface environment and contaminate groundwater resources. However, the transport of engineered nanoparticles through soil is currently not well understood and cannot be modelled in any fundamental manner, placing groundwater resources at risk from nanoparticle contamination. This inability to accurately simulate transport is due to a lack of experimental information on nanoparticle interactions in the pore spaces of real soils.

This thesis illuminates the pore-scale processes governing silver nanoparticle transport through soil. In addition, it examines the influence of surface chemistry and grain/pore distributions on those processes. For the …

Impacts Of Three-Dimensional Non-Uniform Groundwater Flows For Quantifying Groundwater-Surface Water Interactions Using Heat As A Tracer, Jonathan M. Reeves

Masters Theses

Heat-as-a-tracer has become a common method to quantify surface water-groundwater interactions (SW/GW). However, the method relies on a number of assumptions that are likely violated in natural systems. Numerical studies have explored the effects of violating these fundamental assumptions to various degrees, such as heterogeneous streambed properties, two-dimensional groundwater flow fields and uncertainty in thermal parameters for the 1-dimensional heat-as-a-tracer method. No work to date has addressed the impacts of non-uniform, three-dimensional groundwater flows on the use of heat-as-a-tracer to quantify SW/GW interactions. Synthetic temperature time series were generated using COMSOL Multiphysics for a three-dimensional cube designed to represent a …

Efficacy Of Sediment Remediation Efforts On Pah Contaminant Flux Via Porewater Advection At The Sediment-Surface Water Interface, Julie L. Krask, Michael A. Unger, George G. Vadas, Michele A. Cochran, Aaron J. Beck

Presentations

Groundwater advection at the sediment-surface water interface is an important biogeochemical mechanism controlling the transport and bioavailability of contaminants in estuaries. At sites along the Elizabeth River (VA, USA) where the subterranean environment is heavily contaminated with polycyclic aromatic hydrocarbon (PAH)-rich dense non-aqueous phase liquid (DNAPL), consideration of groundwater-surface water dynamics and associated chemical exchange is critical for effective remediation. Preliminary data suggest that porewater advection in permeable sediments at this location is controlled by a host of physical forcing mechanisms that correspond with total flow estimates of up to 15,000 centimeters/year. Here, the efficacy of sediment remediation strategies, including …

Quantifying Groundwater/Surface-Water Interactions In Tributaries To The Wabash River Using Radon‐222 And Other Environmental Isotopes, Philine Bogeholz, Marty Frisbee

The Summer Undergraduate Research Fellowship (SURF) Symposium

Groundwater/surface-water interactions have not been extensively studied in tile-drained watersheds where natural recharge processes are “short circuited” by routing water out of the soil-zone and into nearby drainage ditches. This practice likely impacts baseflow generation in the Wabash River of Indiana. If true, then how is baseflow affected in small tributaries to the Wabash? To answer this question, we investigated groundwater/surface-water interactions in four small tributary drainages to the Wabash River and Sugar Creek. These drainages share common geologic characteristics and are deeply incised providing a window into groundwater flow processes. We sampled these drainages for general geochemistry, radon-222 ( …

Using Bromide Tracer To Measure Uranium Diffusivity In Ground Water Sediments, Francis Michael Tee, Morris E. Jones, Megan K. Dustin, Sharon Bone, John Bargar

STAR Program Research Presentations

More than 129 million liters of groundwater are contaminated with uranium at Old Rifle, Colorado – a former uranium-processing site that operated until 1958. The original Department of Energy (DOE) strategy for remediation, involving natural flushing of U from the groundwater through mixing with surface water, has not proven successful. Thin pockets of silt-, clay-, and organic-rich sediments referred to as naturally reduced zones (NRZs) act both as sinks and sources of U to the aquifer, contribute to plume persistence, and appear to be diffusion limited controlled.

To better understand how the NRZs are diffusion limited controlled, a bromide tracer …

A Hydrogeological Approach To The Status Of Transboundary Ground Water Resources Under International Law [Abstract], Gabriel Eckstein, Yoram Eckstein

Gabriel Eckstein

2 pages. Contains footnotes.

Metal Mobilization In Groundwater, Bauxite, Ar, Steven Alexander Hamlin

Graduate Theses and Dissertations

The Wilcox Aquifer of Bauxite, AR contains bauxite ore deposits that may contribute heavy metals to groundwater. Twenty-four wells were sampled for aluminum, iron, manganese, zinc, lead, barium, nitrate, sulfate, sodium, alkalinity, calcium, magnesium, chloride, pH, total organic carbon, and total dissolved solids. A Wilcoxon Rank-Sum compared the similarity of the three geographic areas covered in the study. All parameters for wells in Bauxite and Sardis failed to reject the null hypothesis, signifying that wells all occupy the Saline Formation. 2/3rds of the parameters from BFI261 and the Bauxite region did not agree, suggesting the two areas do not occupy …

Hydrologic Controls Of Coastal Groundwater Discharge In Southern Taylor Slough, Everglades National Park, Florida, Edward Linden

FIU Electronic Theses and Dissertations

This project empirically determined the controls of groundwater discharge potential and surface water chemistry in southern Taylor Slough, Everglades National Park, Florida. Potential for groundwater discharge was calculated as the difference in equivalent freshwater stage between groundwater and surface water on a daily basis for two sites (upland and coastal) along southern Taylor Slough. Upstream water stages were shown to vary most similarly to the timing of groundwater discharge potential in coastal Taylor Slough. Surface water major ion chemistry did not apparently change as a result of groundwater discharge potential. Surface water major ion chemistry at the coastal site was …

Slides: Wrapping Up The Big Horn Adjudication: Lessons After 38 Years And 20,000 Claims, Ramsey L. Kropf

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Ramsey L. Kropf, Deputy Solicitor for Water Resources, Office of the Solicitor, U.S. Department of the Interior

34 slides

Slides: Never Let A Crisis Go To Waste, Lester Snow

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Lester Snow, Executive Director, California Water Foundation

39 slides

Slides: Perspectives On Water Management In Arizona, Kathy Jacobs

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Kathy Jacobs, Director, Center for Climate Adaptation Science and Solutions (CCASS), Department of Soil, Water and Environmental Science, University of Arizona

25 slides

Slides: Urban Water Reliability And The Salton Sea: Can We Have Both?, Michael Cohen

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Michael Cohen, Senior Research Associate, Pacific Institute

29 slides

Slides: Six Decades Of Texas Water Planning, Ronald Kaiser

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Ronald Kaiser, Professor of Water Law and Policy, Chair of Graduate Water Degree Program, Texas A&M University

32 slides

Slides: New Era Of Water Banking And Refined "Water Accounting", Bonnie Colby

Innovations in Managing Western Water: New Approaches for Balancing Environmental, Social and Economic Outcomes (Martz Summer Conference, June 11-12)

Presenter: Professor Bonnie Colby, Departments of Agricultural and Resource Economics and Hydrology and Water Resources, University of Arizona

23 slides

Groundwater Banking In Imperial Irrigation District: Planning For Future Water Scarcity On The Colorado River, Sara Morton

Master's Projects and Capstones

Urban and rural economies throughout the southwestern United States and Mexico rely on surface water imported from the Colorado River. The Imperial Irrigation District (herein IID or District) has rights to use 3.1 million acre-feet (MAF) per year of Colorado River Water (Regional Water Management Group 2013 and Imperial Irrigation District 2009). Of this water entitlement, IID uses 97 percent for agricultural production. In addition, IID supplies water to San Diego and Los Angeles urban areas.

The population reliant on Colorado River water is expected to rise from approximately 40 million people today, up to 76 million people over the …

Methane Occurrence In Domestic Wells Overlying The Marcellus Shale, Kayla Christian

Theses - ALL

This study explores whether spatial parameters (e.g. landscape position, distance to nearest gas well, geologic unit of water extraction) corresponded with the spatial distribution of methane concentrations in domestic drinking water wells overlying the Marcellus Shale in New York State, where unconventional shale gas extraction is currently banned. Domestic groundwater wells (n=204) were sampled across five counties (Broome, Chemung, Chenango, Steuben, and Tioga) in New York from 2012-2014. Based on analysis of water from homeowner wells sampled in 2013 the majority of samples (77%) had low concentrations of methane (< 0.1 mg/L), and only 5% of wells (n=7) had actionable levels of methane (> 10 mg/L), in the absence of shale gas production. Dissolved …

A Pump Monitoring Approach To Irrigation Pumping Plant Performance Testing, William Merritt Mcdougall

Graduate Theses and Dissertations

Traditionally, irrigation pumping plants have been tested using an instantaneous appraoch, which tests performance parameters over a very short time interval. Using this method, the tester measures the necessary work and energy use parameters to calculate the desired pumping plant performance values. The primary limitation of this approach is its inability to determine the season long efficiency of an irrigation pumping plant.

A new approach to evaluating irrigation pumping plant performance is the use of pump monitoring systems which use high frequency, real-time data collection and telemetry to relay information directly from the pump to the user. This method of …

Deep Groundwater And Potential Subsurface Habitats Beneath An Antarctic Dry Valley, J. A. Mikucki, E. Auken, S. Tulaczyk, R. A. Virginia, C. Schamper, K. I. Sørensen, P. T. Doran, H. Dugan, N Foley

Dartmouth Scholarship

The occurrence of groundwater in Antarctica, particularly in the ice-free regions and along the coastal margins is poorly understood. Here we use an airborne transient electromagnetic (AEM) sensor to produce extensive imagery of resistivity beneath Taylor Valley. Regional- scale zones of low subsurface resistivity were detected that are inconsistent with the high resistivity of glacier ice or dry permafrost in this region. We interpret these results as an indication that liquid, with sufficiently high solute content, exists at temperatures well below freezing and considered within the range suitable for microbial life. These inferred brines are widespread within permafrost and extend …

Model Of Residence Time And Analysis Of Nitrogen Removal For Two Constructed Wetlands At The Franklin Demonstration Farm In Lexington, Illinois, Emma Singh Baghel

Theses and Dissertations

Pollution from nonpoint agricultural runoff has become a major problem facing our streams and rivers today. Not only are fish and aquatic life affected, but so is the quality of our drinking and recreational water resources. Studies have shown that wetlands have proven to be the most cost-effective and low maintenance method of removing nonpoint or diffused contaminate inputs. The biological processes and removal of nutrients in wetlands depend on the total surface area available for microbial activity in the soil and a certain period of water retention time. Since chemical processes take time, the measure of residence time is …

Arsenic Mobilization In An Alluvial Aquifer Of The Terai Region, Nepal, Jasmine Diwakar, Scott Johnston, Edward Burton, Suresh Das Shrestha

Associate Professor Edward D Burton

Study Region

A shallow (<50 m) alluvial aquifer in the Terai region of Nepal.

Study Focus

We examine the hydrogeochemical characteristics of a shallow alluvial aquifer system in the Terai region (Nawalparasi district) to identify possible mechanisms and controls on geogenic As mobilization in groundwater. Groundwater and river water samples from a topo-gradient flow-path and floodplain of a minor river draining the Siwalik forehills were analyzed for physico-chemical parameters.

New Hydrological Insights for the Region

The aquifer is characterized by Ca-HCO₃ type water and is multi-contaminated, with the WHO guideline values exceeded for As, Mn and F in 80%, 70% and 40% of cases respectively. The middle portion …

Quantifying Water Budgets To Evaluate The Hydrologic Performance Of Two Stormwater Detention Ponds In Coastal South Carolina, Samantha Corley

Electronic Theses and Dissertations

Due to their ability to reduce local flooding and protect receiving waters from intense stormwater pulses, stormwater detention ponds are commonly used stormwater management practices. Stormwater engineers construct ponds to moderate peak flow intensities and to allow residence time of the water within the pond to enhance nutrient removal prior to discharging into downstream ecosystems. Yet rarely, if ever, is the functionality of these ponds verified post-construction. This study aimed to compare hydrologic performance of two stormwater detention ponds located in coastal South Carolina to theoretical design plans by assessing a high resolution water budget. Inflow components of the water …

Mapped Karst Groundwater Basins In The Hopkinsville 30 X 60 Minute Quadrangle, James C. Currens, Joseph A. Ray, Phillip W. O'Dell, Robert J. Blair

Map and Chart--KGS

No abstract provided.

Characterization Of Groundwater Discharge In A Back Barrier Tidal Creek, Matthew L. Carter

Electronic Theses and Dissertations

Groundwater discharge in the coastal environment is known to be a complex process. The driving mechanisms of groundwater discharge vary on spatial and temporal scales that can significantly impact coastal water chemistry and play a role in ecological zonation. Evolving combinations of observational and modeling approaches provide a basis to quantify groundwater discharge in a spatial and temporal sense. Here we employ a combination of geochemical (naturally occurring radon isotope) and geophysical (electrical resistivity) techniques to measure groundwater-surface water interactions along a back-barrier tidal creek. In addition to field measurements, a unique non-steady state radon mass balance equation was developed …

Identifying A Mechanism For An Infiltration Threshold From The Sunflower River, Ms To The Underlying Alluvial Aquifer, Austin Cole Patton

Electronic Theses and Dissertations

Long-term groundwater level and stream stage measurements at a USGS coupled groundwater stream-gaging station located on the Sunflower River in Sunflower, MS show an apparent stage-threshold for infiltration to the underlying alluvial aquifer. This site is located near the center of a large regional groundwater cone of depression in the Mississippi River Valley alluvial aquifer. The USGS well (termed well 3 in this study) was thought to be completed in the regional shallow aquifer, though often recording anomalously high water levels relative to other wells in the region. The purpose of this research was to identify the responsible mechanism for …

Nebraska Statewide Groundwater-Level Monitoring Report 2015, A. R. Young, M. E. Burbach, L. M. Howard

Conservation and Survey Division

No abstract provided.

The Effect Of Spatial Patterns Of Soil Hydraulic Conductivity And Depth On Local And Hillslope Scale Shallow Water Table Dynamics, Casey E. Ryan

Graduate Student Theses, Dissertations, & Professional Papers

Much research in forested headwater catchments has focused on the role of topography for organizing subsurface flow and the hydrologic connectivity of upland flow paths to stream networks. However, little work has been conducted to evaluate how localized and hillslope scale patterns of hydraulic conductivity and soil depth contribute to spatial patterns of water table duration, magnitude, and connectivity. I monitored shallow groundwater dynamics in wells distributed across a 1st order hillslope in the Lubrecht Experimental Forest, Montana. Additionally, I collected in-situ measurements of soil saturated hydraulic conductivity and soil depth at 10m intervals across the study hillslope and compared …

Survey Of Two Perfluorinated Organic Compounds (Pfoa And Pfhxa) In Water And Biota Surrounding A Polyfluorinated Chemical Plant, Kevin S. Dillon

Gulf and Caribbean Research

Perfluorooctanoic acid (PFOA) and perfluorohexanoic acid (PFHxA) concentrations were measured in water and biota samples collected within and near a polyfluorinated chemical plant in coastal Mississippi. Effluents from the site and from the local public water treatment plant were sampled along with municipal water supplies, shallow groundwater beneath the site, nearby surface waters, and local biota. Highest concentrations were from stormwater ([PFOA] = 85—530 ng/l; PFHxA = 140—590 ng/l) and shallow groundwaters ([PFOA] = 44—1000 ng/l; PFHxA = 210—3100 ng/l) collected at the site. The local public water treatment effluent also had relatively high PFHxA concentrations (310—590 ng/l). Intermediate PFOA …

Using Modflow To Predict Impacts Of Groundwater Pumpage To Instream Flow: Upper Kittitas County, Washington, Zoe O. Futornick

All Master's Theses

Surface waters in the Yakima River Basin in central Washington are considered over allocated. Since 1960, new water demands have been met through groundwater withdrawals, with most groundwater users holding a later priority date than senior and junior surface water users. As a result of the discussions surrounding this issue, the Upper Kittitas Groundwater Rule has been in effect since 2010. Pumping from new domestic (i.e., permit-exempt or “exempt”) groundwater wells in Upper Kittitas County is not allowed unless mitigation is used to offset the groundwater use. The United States Geological Survey (USGS) has already created a basin-wide model for …

Spatio-Temporal Patterns Of Water Table And Vegetation Status Of A Deserted Area, Limin Duan, Tingxi Liu, Xixi Wang, Yanyun Luo

Civil & Environmental Engineering Faculty Publications

Understanding groundwater-vegetation interactions is crucial for sustaining fragile environments of desert areas such as the Horqin Sandy Land (HSL) in northern China. This study examined spatio-temporal variations in the water table and the associated vegetation status of a 9.71 km² area that contains meadowland, sandy dunes, and intermediate transitional zones. The depth of the water table and hydrometeorologic parameters were monitored and Landsat Thematic Mapper (TM) and Moderate Resolution Imaging Spectroradiometer (MODIS) data were utilized to assess the vegetation cover. Spatio-temporal variations over the six-year study period were examined and descriptive groundwater-vegetation associations developed by overlaying a water table …