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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.
371

A STUDY OF SUBSURFACE VAPOR INTRUSION FROM EXPLORATION & PRODUCTION WASTE

Wascom, Daniel Dawson 14 November 2007 (has links)
Expanding city growth is causing the inhabitants of Louisiana to move further into rural areas. Abandoned oil and gas production sites are being used for residential and light commercial purposes. This thesis will attempt to determine if known benzene levels in Exploration and Production (E&P) waste will be harmful to human health via subsurface vapor intrusion into the newly developed residential and light commercial structures. Louisiana does not currently regulate benzene during the closure of pits that contained E&P waste. Current pit closure techniques warrant testing for benzene Based on current Louisiana legislation, benzene contamination of groundwater is currently the most protected human exposure route to benzene from E&P waste. Indoor air emissions from benzene in E&P waste in the soil must be studied to determine the risks associated to developing residential properties on abandoned exploration and production sites. Exploration and Production waste is described in Louisiana Administrative Code (LAC) 43:Part XIX. Section 129.B as âdrilling wastes, salt water, and other wastes associated with the exploration, development, or production of crude oil or natural gas wells and which is not regulated by the provisions of, and, therefore, exempt from the Louisiana Hazardous Waste Regulations and the Federal Resource Conservation and Recovery Act.â The constituents of concern tested in soil and groundwater, which are currently regulated by Statewide Order 29-B for pit closures are chlorides, petroleum hydrocarbons, and metals. Previous studies of E&P waste are used to determine the characteristics, concentration, and potential harm from benzene to human health found in E&P wastes. These studies were funded by the State and are used in this thesis to provide Louisiana related data. These previous studies of E&P waste are also used as baseline references for known benzene concentrations in E&P waste. A risk assessment outline established by F.B. Thomas in combination with the calculations provided by the Johnson and Ettinger Model (1991) for Subsurface Vapor Intrusion into Buildings are used to estimate the risk of the indoor air exposure to benzene vapors remaining in the soil from closed E&P waste pits.
372

Evaluation of Compliance with the Long Term 1 Enhanced Surface Water Treatment Rule

Douglas, Racquel Rena 16 November 2007 (has links)
Cryptosporidium is a common protozoan parasite that causes cryptosporidiosis, a severe gastrointestinal disease. Currently, there is no antibiotic available to treat the disease. Cryptosporidium has been responsible for several waterborne disease outbreaks in the United States. The largest cryptosporidiosis outbreak in United States history occurred in Milwaukee, Wisconsin in spring 1993. The vulnerability of the United State drinking water supply to waterborne disease outbreak is still prevalent nearly 15 years after the Milwaukee outbreak. In order to effectively control Cryptosporidium, the EPA has strengthened the regulations on turbidity control for filtration performance by implementing the Long Term 1 Enhanced Surface Water Treatment Rule. The Long Term 1 Enhanced Surface Water Treatment Rule applies to all public water systems that serve fewer than 10,000 people and use surface water or ground water under the direct influence of surface water. The turbidity level of combined filter effluent water samples must be less than or equal to 0.3 NTU in at least 95% of the measurements taken each month, with no samples exceeding 1 NTU. Systems meeting these filter performance requirements are presumed to achieve at least a 2-log removal (99%) of Cryptosporidium. The purpose of this research is to evaluate compliance with the Long Term 1 Enhanced Surface Water Treatment Rule for a potable water treatment system operated by an oil refinery in southeast Louisiana that has been experiencing turbidity spikes since February 2006. The turbidity and disinfection data obtained from this facility will be examined. This study found that, despite meeting compliance requirements of the Long Term 1 Enhanced Surface Water Treatment Rule, there were still several areas of concern within the treatment process. Additional information is needed to determine the effectiveness of the turbidity data management tool. The regression analysis showed that raw water turbidity could not accurately predict daily average turbidity. Recommendations were made regarding comprehensive system evaluation, monitoring, improvements in treatment technique, and best practices. Although this study concluded in September 2006, significant improvements were made to the gravity sand filters. In April 2007, an ultrafiltration system replaced the gravity sand filters in the potable water treatment system.
373

Ethanol Production Using Continuous Multi-staged Immobilized Microbe Bioreactors: A Laboratory Study

King, William Bruce 18 January 2008 (has links)
Alternative fuels are important for the United States to reduce their dependence on fossil fuels. Currently, ethanol is the only renewable fuel that is produced in commercial quantity. The demand for ethanol is increasing throughout the world. The production of ethanol is limited by the available feedstocks and processing technology. Corn is the primary feedstock for ethanol in the United States. It is processed in either the wet milling or dry milling process. Both processes use either the batch or continuous fermentors. Both batch and continuous systems have operational restrictions with maintaining a good growth of yeast and preventing contamination with bacteria. The use of Immobilized Microbe Bioreactors will provide a continuous system that maintains a growth of yeast and is resistant to bacteria. The Immobilized Microbe Bioreactors are packed with biocarrier which is a solid, porous, inorganic substance that provides a large surface area for attachment of the yeast cells. The yeast colonizes the internal surfaces as well as the external surfaces of the biocarrier. This provides a higher culture density of yeast which is resistant to bacterial contamination. The feasibility of using the Immobilized Microbe Bioreactor was addressed by laboratory testing. Raw sugar and molasses were used as feedstocks. The Microbubble Generator was tested for the ability to saturate the feed with air to facilitate the growth of yeast. The yield of ethanol was determined by distilling azeotropic ethanol as an overhead product. The data indicated that the Immobilized Microbe Bioreactor could be an improvement to ethanol production systems.
374

Comprehensive Planning in Louisiana

Maloney-Mújica, Lynn A 22 January 2008 (has links)
This study explores the factors associated with the implementation of land use planning policies and tools among the parishes (counties) of Louisiana. There is an absence of statutory standards, strict guidelines, and other external drivers for planning in Louisiana and the extent to which local governments regulate land use varies widely among local jurisdictions. The purpose of this study is to provide an empirical model of intrinsic factors that might explain why some parishes have decided to intervene in land use by adopting a high number of planning policies and tools, and why others have failed to adopt few, if any. A planning score derived from the number of land use planning policies and tools that have been formally adopted is tested against variables for socio-economic, environmental pressure, and government administration conditions using an Ordinary Least Squares (OLS) Multivariate Analysis. The empirical evidence indicates that the adoption of planning policies and tools is least associated with non-metropolitan parishes with police jury forms of government. Results also indicate that high median housing value is the factor most associated with a high planning score even after accounting for metro areas, where land values are proportionately higher. There is also a strong positive association between the planning score and the amount of surface water within a jurisdiction. These findings, and the fact that no relationship between planning and population, growth, or education was found, advances the theory that the impetus for planning at the local level in Louisiana is based on the protection of property and property values rather than growth. This theory suggests that a focus on floodplain protection and mitigation, water resource conservation and preservation, and water-dependent recreation and tourism could be the best method for encouraging planning policy adoption by local governments.
375

Wetland Mitigation Banks and the No-Net-Loss Requirement: An Evaluation of the Section 404 Permit Program in Southeast Louisiana

Tyrna, Abbey Anne 10 April 2008 (has links)
Section 404 of the Clean Water Act provides regulatory oversight for wetland conservation. One goal of the Section 404 program is to achieve a no-net-loss of the remaining wetland acres and functions. Wetland mitigation banks have been incorporated into wetland policy because of their potential advantage in achieving the no-net-loss requirements. This study analyzed four wetland mitigation banks with credits sold between 1991 and 2007 in southeastern Louisiana to determine if they were contributing to the goal of no-net-loss. The goal of no-net-loss is reached when there is complete compensation of wetland structure and function. The study area for this research was Liberty Bayou-Tchefuncta Basin, USGS Cataloging Number 0809020. A structural comparison between bank wetlands and those permitted was made using data collected from permits and from authoritative bank documents on wetland size and vegetation. A functional assessment of the wetlands was conducted through hydrogeomorphic classification using a geographical information system to integrate information on their geology, ecoregion, slope, and soils. Wetland functional performance was calculated using wetland habitat quality and mitigation ratios as variables. The results from the permit data showed that 2,546 acres (850 ha) of mitigation was required to replace 2,309 acres (932 ha) of impacted wetlands, creating an additional 238 acres (96 ha) of required mitigation. Ninety-five percent of the wetlands lost were replaced with wetlands that had similar vegetation. Furthermore, the hydrogeomorphic classification illustrated that 99% of all permitted wetlands were also functionally similar to their mitigated counterparts. The mitigation ratios used to calculate functional performance showed a functional loss of 2,505 acres (1,014 ha). A positive wetland trade is revealed when looking at wetland structure alone. However, the functional assessment indicates a negative functional trade between the permitted wetlands and the mitigated wetlands. The cumulative effect of a loss in wetland functions could be a degraded watershed that provides inferior water quality, habitat quality, water storage capacity, etc. The mitigation requirements were found to be inconsistent leading to a high functional loss for the basin. Permitted impacts under Section 404 could be better managed if a standardized method for calculating mitigation ratios was implemented.
376

The Impact of the Caernarvon Diversion on Above- and Belowground Marsh Biomass in the Breton Sound Estuary after Hurricane Katrina

Moerschbaecher, Matthew Korbel 11 June 2008 (has links)
The purpose of this project was to monitor the recovery of marsh vegetation following Hurricane Katrina in the Breton Sound estuary, which is directly influenced by the Caernarvon freshwater diversion. From March 2006 until October 2007, we measured above- and belowground biomass, soil porewater nutrients (NOx, NH4, and PO4), porewater salinity, porewater sulfide concentrations, and soil redox potential bimonthly at duplicate Near (N), Intermediate (M), and Far (F) sites (with respect to the diversion), as well as at a Reference (C) site. End of season live (EOSL) below and above ground biomass was measured at 26 separate stations where vegetation studies had been done previously. Peak standing crop ranged from 423 g/m2/yr at site M2 to 1515 g/m2/yr at F1. Aboveground biomass was significantly greater at N1 than at N2, M1, or M2. Peak belowground biomass ranged from 8315 g/m2/yr at C2 to 17890 g/m2/yr at N1. Multiple regression analysis showed that sulfide levels were related to the amount of belowground biomass (p < 0.05; R2=0.13). PO4 concentration was related to the amount of aboveground biomass (p<0.05; R2=0.09). Short term vertical marsh accretion measurements ranged from 0.49 cm y-1 at N2 to 1.25 cm y-1 at N1, suggesting that all the study sites are stable or accreting at a rate which offsets local RSLR. Analysis of the results of short term accretion compared to regional relative sea level rise (RSLR) indicates that all Caernarvon sites are keeping pace with RSLR. Analysis of porewater parameters showed that stress on plants was low to moderate while nutrient concentrations were greatest at the Near sites.
377

Land Use and Water Quality Characterization of Boeuf Basin, LA

LeBlanc, Joseph Wesley 09 July 2008 (has links)
The three primary goals of this project were to establish the ambient background of water quality in the Lake Boeuf basin in southeast Louisiana; establish land use patterns in the basin and the relation to water quality; and develop a preliminary plan to improve water quality through the use of best management practices and wetland assimilation. Urban and agricultural acreage borders the basin and runoff from these lands forces loadings of nutrients into the adjacent canals where they become channelized and ultimately exit the Boeuf Basin into Lac des Allemandes. From September 2007 until February 2008, water sampling occurred monthly at twelve discrete locations throughout the study area. These samples were tested for NOx, PO4, Si, NH4, salinity, TSS, TN, and TP. Results of this data showed concentrations in the basin were not extraordinarily high. Sites located nearer to sugarcane acreages showed higher nutrient concentrations as compared to other sampling sites. Field data was compared to an existing dataset compiled by the Louisiana Department of Environmental Quality for use in establishing total maximum daily loads for the basin. Statistical analysis revealed significant decreases of PO4 and salinity concentrations from years 2000 through 2008. A yearly nutrient load estimate for the basin was established for NOx, NH4, TKN, TN, and TP. Using cited nutrient removal curves, it was determined that the available wetland acreage in Boeuf Basin could assimilate these loads achieving nearly 100% removal. Reductions in nutrient loads can be achieved by implementing best management practices in the adjacent agriculture. Other solutions include reducing direct flow from sugarcane field drainage ditches and diversion of this drainage through the wetlands allowing for assimilation.
378

An Analysis of the Benefits and Patterns of Public Support for Urban Forestry Programs

Landano, Barbi Marisa 14 July 2008 (has links)
Trees are an essential element in a healthy urban community. They provide many benefits if they are properly managed and maintained throughout their lives. In order to accomplish this, urban forestry programs need to be established and there needs to be a good support system within the city. The objectives of this study are to identify key factors that may influence public support for urban forestry programs and to examine the role of nonprofit organizations in building support for and implementing urban forest programs. Surveys of Baton Rouge, Louisiana residents were conducted to identify the variables that are associated with residents willingness to pay for urban forestry programs. Survey responses indicated that that a desire to maintain a healthy environment for future generations is consistently associated with willingness to pay for urban forestry enhancement efforts and that support from the general public can be better obtained when people are aware of the benefits they will receive from properly planted trees. A street tree inventory also was conducted to estimate the benefits that the existing trees provide to residents of the Old South Baton Rouge community and how a nonprofit organization such as Baton Rouge Green can facilitate the effectiveness of a citys urban forestry program. These findings demonstrate that nonprofit organizations are a strong component of urban forestry because they can help to educate the public, bring the community together and plant the right tree in the right place to obtain optimal benefits.
379

An Evaluation of the Perceived Obstacles for Policy Officials Regulating the Post Harvest Treatment of Raw Oysters to Control the Human Health Vibrio vulnificus Problem

Oestringer, Amy Leah 14 July 2008 (has links)
Vibrio vulnificus is the leading pathogen linked to seafood-associated deaths. This naturally occurring marine bacterium presents a human health risk when it is consumed in raw oysters. Hospitalization is necessary in 90 % Vibrio vulnificus illnesses and 40% end in death. (CDC) Several guidelines and regulations have been enacted to combat this human health issue, but have failed to reduce the steadily rising illness rate. Post-harvest processing requirements for raw oysters could be used to reduce illness rates. A survey was conducted to measure the perceived obstacles that regulators and industry representatives of the raw oyster industry face in policymaking to implement more stringent post harvest requirements. Members of the Florida, Alabama, Mississippi, Louisiana, Texas and California departments of health and fisheries were surveyed as well as restaurant owners across Louisiana. By examining the attitudes and perceptions of both of these groups of stakeholders, better methods of policy implementation can be derived. The objectives of this thesis are to determine if previous education efforts are reaching the industry representatives, to determine what the perceived obstacles to implantation of more stringent post-harvest processing standards are and to determine how perceptions among regulators and industry affiliates vary. The data showed that perceptions among these stakeholders diverged on several obstacles. Education efforts were shown to be ineffective alone. Resistance to additional regulation by the oyster industry was indicated as a major obstacle to the implementation of post harvest processing requirements. Cost to the producer was also cited as a major obstacle to these additional regulations. The information collected from this preliminary study has shown several areas where policy could be improved.
380

Influences on Effective Local Wildfire Mitigation Programs

Geaghan, Kimberly Ann 14 July 2008 (has links)
The purpose of this research is to identify key components of community wildfire risk reduction programs and potential influences on the adoption of these program elements. Community wildfire programs have been developed to educate and encourage property owners to adopt vegetation management practices such as creating defensible space around structures, landscaping with fire-resistant plants, and removing potential wildfire fuels such as trees and shrubs. The analyses are based on a survey conducted by investigators from Louisiana State University in conjunction with the U.S. Forest Service. This survey was distributed to wildfire mitigation program managers listed on the National Wildfire Programs Database website. A Principal Component Analysis (PCA) was conducted on the data returned from this sixty-nine-item survey. A range of socioeconomic variables was gathered from the 2000 Census Bureau and was used along with a fire history variable created from data extracted from the survey to examine the extent to which the variables are associated with program development. Five factors were identified from the PCA as being indicators of key components of risk-reduction programs. Local programs with these elements are assumed to have a greater capacity for effectively reducing or mitigating wildfire risks to communities within the wildland-urban interface (WUI). The factors are more local regulations and codes, larger numbers of public education, vegetation disposal, risk assessment activities and fewer reported problems with program funding. These factors were regressed with demographic variables selected for each survey respondents geographic area. Several different demographic variables were found to be significantly associated with the selected factors. These are population density, property value, wealth, percent of homeownership, percent of population with a college degree, and population change. Formulation and implementation of these desirable program components were found to be associated with slower growing, less densely populated communities, and those with wealthier and better educated residents.

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