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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A VALIDATION STUDY OF THE NORTH CAROLINA RAPID FIELD-BASED RATING SYSTEM FOR DISCRIMINATING FLOW PERMANENCE CLASSES OF HEADWATER STREAMS IN AGRICULTURE BASINS IN SOUTHERN ILLINOIS

Lampo, Miles 01 August 2015 (has links)
Rapid field-based assessment methods for classifying stream permanence in headwater streams are needed to accurately inform regulatory decisions regarding which streams are protected under the Clean Water Act. In North Carolina, a rapid field-based assessment method for identification of intermittent and perennial streams has been developed. The North Carolina Method (NC method) uses 26 attributes divided into three categories geomorphology, hydrology, and biology to assess a particular study reach's flow permanence. In this method, the attribute scores for a given study reach are totaled and the sum of the score is used to rank the reach as ephemeral, intermittent, or perennial. The study objective were to (1) evaluate the NC method's ability to classify the flow permanence of agricultural, low order, study reaches in Southern Illinois and (2) create empirical models that predict flow permanence at a given stream location. The results of the study show the NC method successfully differentiated ephemeral from intermittent and perennial study reaches 100% of the time. However, there was lower fidelity in differentiating between intermittent and perennial study reaches and correctly determined flow permanence 82% of the time. In two of the cases where the NC method categorized the streams incorrectly, the score was on the threshold between intermittent and ephemeral. If these study reaches were categorized during a drier period they may have scored correctly. These results suggest the NC method would be a strong foundation for the development of a rapid field-based assessment protocol method for Illinois. Regression models were developed to predict NC method scores using a variety of hydrologic, geomorphic, and land-cover metrics. Two statistically significant models (>95% confidence interval) for estimating NC method stream permanence scores were developed using these physical parameters. One of the significant regression models developed used watershed area alone as a predictor of the NC method stream permanence scores. The second significant regression model employed bankfull width, upslope surface-water area, and upslope area of grass lands. These models explained 61% and 69% of the variance in the NC method stream-permanence scores, respectively. While the regression models develop here are not capable of explicitly modeling stream-permanence class with a high degree of accuracy, they are useful for guiding stream-permanence study-site selection.
2

The Trouble with Assumptions: An Analysis of the Ongoing Struggles with §404 Assumption

Carlos, Aileen 17 October 2014 (has links)
The Clean Water Act's §404 allows states to assume control of wetland dredge-and-fill permitting from the Federal Government. However, since the bill was passed in the 1970's, only two states have successfully assumed control of the permitting program. Each state that has looked into assumption has run into barriers, issues, and problems that have prevented them from successfully assuming the program. I interviewed people involved with assumption at different levels of involvement, and this thesis seeks to provide a conflict management design system that will help states overcome some of the most pernicious issues.
3

THE HISTORICAL DEVELOPMENT OF NATIONAL NONPOINT SOURCE POLLUTION ABATEMENT EFFORTS AND THE ROLE OF FEDERALISM

Stazyk, Edmund C. 05 October 2006 (has links)
No description available.
4

A Study of How Changes to the Clean Water Act May Affect “Isolated” Wetlands in Hamilton County, Ohio

Thomas, Cory Alan January 2005 (has links)
No description available.
5

Sediment Management for Aquatic Life Protection Under the Clean Water Act

Govenor, Heather Lynn 19 January 2018 (has links)
Although sediment is a natural component of stream ecosystems, excess sediment presents a threat to natural freshwater ecosystems. Sediment management is complicated because sediment can be dissolved in the water column, suspended as particles in the water column, or rest on the bottom of the stream bed, and can move between these forms (e.g. bedded sediment can be resuspended). Each form of sediment affects aquatic life in a specific way. To manage stream sediment in a way that protects aquatic life, we need to understand the ways different forms of sediment affect living things, and we need to be able to predict how sediment changes form under different stream conditions (for example, during high water events). To improve our understanding of these things, the studies in this dissertation set out to: (1) identify how often sediment is specifically mentioned as the primary pollutant “stressor” of the benthic macroinvertebrate community (primarily aquatic insects); (2) determine which forms of sediment have the largest negative impacts on aquatic insects in Virginia and what levels of sediment may cause harm; and (3) measure the changes of sediment between suspended and bedded forms in a small stream to provide information needed to restore the health of stream ecosystems. An inventory of published US Clean Water Act Total Maximum Daily Load (TMDL) reports, which states write to identify their impaired waters and their plans to improve those waters, revealed that sediment is an important stressor in over 70% of waters that have altered aquatic insect communities. If the language used to describe how waters are evaluated and what is causing the impairments were standardized among states, data collected under the Clean Water Act could be more broadly used to help understand water quality issues and ways to address them. Analysis of 10 years of Virginia Department of Environmental Quality sediment and aquatic insect community data collected within 5 ecoregions of the state indicates that a combination of 9 sediment parameters reflecting dissolved, suspended, and bedded forms explains between 20.2% and 76.4% of the variability in the health of the aquatic insect community within these regions. Embeddedness, which measures how much larger particles such as gravel and cobble are buried by finer particles like sand; and conductivity, which is a measure of dissolved salts in the water column, both have substantial impacts on the aquatic insect community. Sensitivity thresholds for embeddedness and conductivity indicate the levels of these parameters above which 5% of insect families are absent from a stream; therefore, these levels are considered protective of 95% of the insect community. Thresholds for embeddedness are 68% for the 5 combined ecoregions, 65% for the Mountain bioregion (comprised of Central Appalachian, Ridge and Valley, and Blue Ridge ecoregions), and 88% for the Piedmont bioregion (comprised of Northern Piedmont and Piedmont ecoregions). Thresholds for conductivity are 366 µS/cm for combined ecoregions, 391 µS/cm for the Mountain bioregion, and 136 µS/cm for the Piedmont bioregion. These thresholds can be used by water quality professionals to identify waters with sediment impairments and can be used to help identify appropriate stream restoration goals. A study of sediment movement within the channel of a small stream indicated average transport speeds of ~ 0.21 m/s during floods with peak flows of ~ 55 L/s. The use of rare earth elements (REE) to trace sediment particles revealed individual particle transport distances ranging from 0 m to >850 m. Deposition on a unit area basis was greater in the stream channel than on the floodplain, and the movement of sediment from the stream bed to the water column and back again during sequential floods was evident. Approximately 80% of the tracer was deposited within the first 66 m of the reach. This information can aid the development of models that predict the impact of stream restoration practices on in-stream habitat and improve predictions on the time it will take between the initiation of stream restoration projects and when we see improvements in the biological community. / PHD
6

Neoliberalism, the Environmental Protection Agency, and the Chesapeake Bay

Steffy, Kathryn Marie 30 June 2016 (has links)
Neoliberalism, as the influence of economic considerations within the political process, has impacted environmentalism on a variety of levels. Without regulation, the neoliberal capitalist drive to maximize production, consumption, and profits is antagonistic to environmental sustainability. The influences that corporations and economic elites have within modern democracies holds substantial implications for the rigor and enforcement of environmental policies. Particular to the United States, the Environmental Protection Agency offers numerous illustrations of neoliberal influence within its history and policy practices. These influences inevitably impact the Agency's ability to accomplish the goals of their mission and purpose statements. As seen through regulations such as the Clean Water Act, neoliberal pressure has altered the priorities of government on a federal level to prioritize economic well-being over that of other social goods, such as environmental protection. The Clean Water Act prioritizes economic profitability over environmental protection through cap and trade policies, such as NPDES permits, and legitimizes pollution-causing behavior through TMDLs. Further, the act was weakened by neoliberal forces with the non-point source exemption created for the sake of avoiding economic harm to large industries and its shortcomings are visible within many of the nation's waterways, including the Chesapeake Bay. Through a case study, this project demonstrates how the neoliberal influences impacting the Environmental Protection Agency has resonated in its policies, like in the abilities of the Clean Water Act to sufficiently clean-up the Chesapeake Bay within its proposed timeline. / Master of Arts
7

High-Frequency Nitrate Monitoring in Dynamic River Systems: the Case of Three Iowa Rivers in the Mississippi Basin

Banerjee, Malini De 01 July 2013 (has links)
High frequency water quality monitoring presents unique and unlimited opportunities of exploring spatio-temporal variation in water quality. Knowledge gained from analyzing high frequency water quality data can provide more clarity regarding transportation and processing of water constituents over time and space and scale. This study analyzes high frequency discharge, nitrate load and concentration data for three watersheds of different sizes - Cedar River Watershed, North Raccoon and Middle Raccoon. Each of these sites were monitored for 2-3 calendar years. Sudden spikes in discharge, nitrate concentration and load data, also defined as "events" were analyzed in great detail to understand the patterns in event occurrence and event intensity. Smaller watersheds seemed to have sharper and "flashier" events compared to bigger watersheds. Nitrate concentration events were flatter in shape compared to discharge and nitrogen load events. The relationship between nitrogen concentration and discharge was found to be varying over time, unlike the relationship between nitrate load and discharge, which were almost perfectly correlated for most site-year combinations. Based on more than 40,000 simulations, it was determined that high frequency water quality sampling is not only efficient in capturing minute spatio-temporal variations but can also capture nitrate exceedances to a greater degree. High frequency sampling was also associated with higher yield ratio in nitrate load estimates, not only during high flow periods, but also during the non-high-flow period.
8

Characterization of Section 404 Permit Mitigation Plans, Coastal Margin and Associated Watersheds, Upper Texas Coast

Conkey, April A. 14 January 2010 (has links)
A predicted loss of agricultural rice-wetlands and increasing urbanization and development threatens the remaining freshwater wetlands along the upper Texas coast. To avoid, minimize, and mitigate wetland loss, the U.S. Army Corps of Engineers (Corps) is directed to enforce Section 404 of the Clean Water Act (1975 amendment) by administering permits for development. Furthermore, a 1990 Memorandum of Agreement (MOA) between the Corps and the U.S. Environmental Protection Agency (EPA) proposed a national goal of no net wetland loss (NNL). My goals were to identify the frequency of occurrence of freshwater wetland loss due to dredge or fill, assess final plans to mitigate wetland loss, and verify the persistence of the created compensatory wetlands. I created a database of 96 individual, Section 404 permits issued from 1981 to 2001 in the counties of Chambers, Hardin, Jefferson, Liberty, Montgomery, Orange, and San Jacinto (Galveston District Office, U.S. Army Corps of Engineers). Descriptive statistics were calculated for permit characteristics in relation to issue date (pre- or post-NNL). Public comments received from national and state agencies were rank ordered against mitigation plan type to determine Spearman's Rank Order Correlation Coefficient. Visual identification (via site visits and 1996 aerial photos) was used to validate compensatory wetland persistence. Shoreline protection of private property and oil and gas drilling (64% of permit applicants and 59% of impacts) had the greatest effect on wetland loss in the region, particularly Chambers, Jefferson, and Montgomery counties. Overall, 79.3 ha of freshwater wetlands were gained; however, gain was overestimated due to large projects for habitat enhancement. Permits issued post-NNL were more likely to have formal mitigation plans (58% vs. 13% pre-NNL) and allowed no net wetland loss. Although agency comments recommending more formal mitigation plans increased after NNL, only a weak positive correlation was detected (Spearman's r less than or equal to 0.4). Six of seven created wetlands remained in existence through 2006 though they are freshwater ponds replacing more diverse aquatic systems. I recommend the development of a comprehensive method to track wetland loss, mitigation, and changes in watersheds over time.
9

Characterization of Section 404 Permit Mitigation Plans, Coastal Margin and Associated Watersheds, Upper Texas Coast

Conkey, April A. 14 January 2010 (has links)
A predicted loss of agricultural rice-wetlands and increasing urbanization and development threatens the remaining freshwater wetlands along the upper Texas coast. To avoid, minimize, and mitigate wetland loss, the U.S. Army Corps of Engineers (Corps) is directed to enforce Section 404 of the Clean Water Act (1975 amendment) by administering permits for development. Furthermore, a 1990 Memorandum of Agreement (MOA) between the Corps and the U.S. Environmental Protection Agency (EPA) proposed a national goal of no net wetland loss (NNL). My goals were to identify the frequency of occurrence of freshwater wetland loss due to dredge or fill, assess final plans to mitigate wetland loss, and verify the persistence of the created compensatory wetlands. I created a database of 96 individual, Section 404 permits issued from 1981 to 2001 in the counties of Chambers, Hardin, Jefferson, Liberty, Montgomery, Orange, and San Jacinto (Galveston District Office, U.S. Army Corps of Engineers). Descriptive statistics were calculated for permit characteristics in relation to issue date (pre- or post-NNL). Public comments received from national and state agencies were rank ordered against mitigation plan type to determine Spearman's Rank Order Correlation Coefficient. Visual identification (via site visits and 1996 aerial photos) was used to validate compensatory wetland persistence. Shoreline protection of private property and oil and gas drilling (64% of permit applicants and 59% of impacts) had the greatest effect on wetland loss in the region, particularly Chambers, Jefferson, and Montgomery counties. Overall, 79.3 ha of freshwater wetlands were gained; however, gain was overestimated due to large projects for habitat enhancement. Permits issued post-NNL were more likely to have formal mitigation plans (58% vs. 13% pre-NNL) and allowed no net wetland loss. Although agency comments recommending more formal mitigation plans increased after NNL, only a weak positive correlation was detected (Spearman's r less than or equal to 0.4). Six of seven created wetlands remained in existence through 2006 though they are freshwater ponds replacing more diverse aquatic systems. I recommend the development of a comprehensive method to track wetland loss, mitigation, and changes in watersheds over time.
10

Economic Assessment of Compliance Costs for Ontario Pig Producers Under Nutrient Management Regulations

Beechey, Nicole Elizabeth 16 January 2012 (has links)
This study investigates the impact of nutrient management regulations on pig farms in Ontario, Canada. Using mathematical programming, small, medium and large farrow to finish and finishing pig farms are examined using uniform and crop requirement based manure application. The model scenarios characterize the cost of compliance when nutrient application standards are applied from the Nutrient Management Act and a previously proposed standard from the Clean Water Act. Compliance costs for scenarios with uniform manure application are ≤6.47%; while compliance costs for scenarios with crop requirement based manure application are ≤0.25%. The Nutrient Management Act has two calculations for nutrient application standards, producers must comply with the less binding calculation. Compliance costs for producers under the less binding standard following a uniform manure application strategy are ≤1.53%; while producers following a crop requirement based manure application strategy have no compliance costs. The proposed Clean Water Act standard is more restrictive than the Nutrient Management Act standards. / Ontario Pork, OMAFRA

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