Thesis (M.S.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / 2031-01-01

Thesis (M.A.)--State University of New York at Binghamton, Dept. of Geological Sciences and Environmental Studies, 2005. / Includes bibliographical references.

Measurement and analysis of aquifer-system compaction have been used to characterize aquifer and confining unit properties when other techniques such as flow modeling have been ineffective at adequately quantifying storage properties or matching historical water levels in environments experiencing land subsidence. In the southeastern Coastal Plain of Virginia, high-sensitivity borehole pipe extensometers were used to measure 24.2 mm of total compaction at Franklin from 1979 to 1995 (an average of 1.5 mm/yr) and 50.2 mm of total compaction at Suffolk from 1982 to 1995 (an average of 3.7 mm/yr). Analysis of the extensometer data reveals that the small rates of aquifer-system compaction appear to be correlated with withdrawals of water from confined aquifers. One-dimensional vertical compaction modeling indicates that the measured compaction is the result of nonrecoverable hydrodynamic consolidation of the fine-grained confining units and interbeds as well as recoverable compaction and expansion of coarse-grained aquifer units. The modeling results also provide useful information about specific storage and vertical hydraulic conductivity of individual hydrogeologic units. The results of this study enhance the understanding of the complex Coastal Plain aquifer system and will be useful in future modeling and management of ground water in this region. / Master of Science

Thesis (M.S.)--University of Nevada, Reno, 2004. / "December, 2004." Includes bibliographical references (leaves 79-83). Online version available on the World Wide Web.

Thesis (Ph. D.)--University of Nevada, Reno, 2007. / "May, 2007." Includes bibliographical references (leaves 307-323). Online version available on the World Wide Web.

Watersheds within northwestern Mississippi, a productive agricultural region referred to as the Delta, were recently identified as contributors of total nitrogen and phosphorus fluxes to the Gulf of Mexico. Water withdrawals for irrigation in the Delta have altered flow paths between surface-water and groundwater systems, allowing for more surface-water losses to the underlying alluvial aquifer. In order to understand how to manage nitrogen in a watershed, it is necessary to identify and quantify hydrologic flow paths and biogeochemical conditions along these flow paths, which ultimately combine to determine transport and fate. In order to evaluate the extent and role of surface-water losses to the alluvial aquifer on the transport of nitrate, a two-dimensional groundwater/surface-water exchange model was developed for a site within the Delta. Results from this model determined that groundwater/surface-water exchange at the site occurred regularly and recharge was laterally extensive into the alluvial aquifer. Nitrate was consistently reported in surface-water samples (n= 52, median concentration = 39.8 micromol/L), although never detected in samples collected from instream or near stream piezometers (n=46). Coupled model and water-quality results support the case for denitrification/ nitrate loss from surface water moving through an anoxic streambed. At larger scale, recent results from two Spatially Referenced Regressions on Watershed attributes (SPARROW) models imply that nitrogen is transported relatively conservatively once it enters the main channel of the Big Sunflower River Basin, which contributes much of the water discharging from the Yazoo River Basin to the Mississippi River. Net loss of nitrogen was assessed by comparing total nitrogen data from Lagrangian sampling events to chloride, drainage area, and predicted total nitrogen flux results from the SPARROW models. Results indicated relatively conservative instream transport of nitrogen at the scale of the Big Sunflower River Basin; however, two potential nitrogen loss mechanisms were identified: (1) transport and transformation of nitrogen through the streambed, and (2) sequestration and transformation of nitrogen above the drainage control structures downstream of Anguilla.

This study explores key aspects of water usage in Virginia via a broad-scale analysis of multiple water users through thirty years of time-series records from the Virginia Water Use Data System. A full spectrum of users is considered, including water used for energy, industrial, agricultural and municipal applications. The extent of the relationship between the volume of water used and drivers like economic and climatic conditions are not well defined in humid environments like Virginia. Mann-Kendall testing is applied to identify water use trends through time both statewide and at the county level. A panel regression is employed to identify relationships between water use and explanatory variables of climatic and economic conditions, both spatially and temporally. Key trends include that industrial and energy sector water withdrawals per facility are significantly decreasing over time. Water used for agricultural applications was found to increase on warmer than average years and decrease on wetter than average years, indicating the panel regression methodology successfully demonstrated and quantified intuitive trends. Interestingly, municipal and industrial water usage had a statistically significant relationship with the Gini coefficient, a measure of inequality in rainfall distribution, indicating intraseasonal variability may play an important role in water use trends that is not apparent using seasonal averages alone. Overall, this work contributes to the understanding of water use trends at the state level for Virginia, and better characterizes long-term trends and short-term variability in water withdrawal. / MS / This work applies statistical methods to better understand water use trends through time and across the state of Virginia. The primary data source is a record spanning thirty years of water use, reported by more than 2,400 users in all counties of Virginia to the Department of Environmental Quality (VDEQ). This analysis includes a full spectrum of water sectors, including water used domestically (municipal), water used for manufacturing (industrial), agriculture applications and water used in the production of energy. The first objective is to determine if water use, normalized by changes in population and the number of users, is increasing or decreasing over time for each county in Virginia. Once the trends through time are identified, the next objective is to better define the underlying factors (explanatory variables) which may drive changes in how much water is used. One potential factor includes changes in the economic conditions. For example, the economic recession in 2008 caused some decline in industrial production. Did this likewise cause a reduction in water used by industrial facilities? Particularly, the analysis considers how the annual average temperature, total annual precipitation, rainfall variability and the length of heatwaves that occur in a given year might impact the amount of water withdrawn in that year. This work addresses a knowledge gap about how water use is impacted by climate change in humid environments like Virginia. This work aims to establish whether or not there is a significant relationship between time, climate, economic change and water use in Virginia. The trends identified in this study will support the management of water supplies in Virginia and the development a more informed state water resources plan.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 100-108). Also available on the World Wide Web.

The water in most reservoirs is density stratified with depth. This stratification leads to the inhibition of vertical movement, consequently, when water is withdrawn from the reservoir it tends to move in a jet-like layer called a withdrawal layer, towards the sink. By placing the sink at a certain depth, one is able to selectively withdrawal water from a limited range of depths and thus obtain water of a desired quality. Much work has been done in this field by considering a simplified boundary geometry, usually rectangular. However little attention has been given to the effects of accurate boundary geometry. For this thesis, five numerical experiments were conducted for the problem of a two-dimensional, viscous, incompressible, slightly-stratified flow towards a sink in a triangular reservoir. / Science, Faculty of / Mathematics, Department of / Graduate

In the United States, one in every 100 adults is confined to a correctional facility. Approximately 60% of inmates have an alcohol use disorder (AUD). When compared to the general population, inmates are twice as likely to have AUD. As they are unable to readily access alcohol, inmates entering a correctional facility with AUD are at high risk for the lethal alcohol withdrawal syndrome (AWS). AWS is preventable and yet correctional nurses process new inmates without an evidence-based clinical practice guideline (CPG) to assess for AUD, the prerequisite for AWS. The purpose of this project was to develop an evidence-based CPG with implementation algorithm to guide the inmate assessment for AUD. The ACE star model of knowledge transformation guided the project, the AGREE II was used to develop the CPG, and the Delphi technique was used to evaluate the final CPG with algorithm. Nationally, 20 correctional health experts were identified and asked to participate in the Delphi expert panel, although 11 experts agreed to participate only 9 completed the evaluation. The experts were correctional health experts, nurses and physicians, from different regions of the United States. The resulting CPG satisfied all 23-items of the AGREE II. Through 2 Delphi panel rounds, all participants recommended the CPG with minor modifications (6 experts recommended as presented while the 3 recommended with modifications). At the project conclusion, all 9 experts agreed the CPG will help improve the identification, referral, and management of inmates with AUD. This project contributes to positive social change as the CPG addresses a serious problem, AUD with possible AWS, in a vulnerable population. The CPG may be generalizable for use in other correctional facilities.