<p>We have developed and applied novel experimental techniques for determination of thermodynamic and kinetic properties of semi-volatile organic aerosols. The thermodynamic properties investigated were the saturation pressure, enthalpy of vaporization and activity coefficient, and the kinetic property was the evaporation coefficient.</p><p>The thermodynamic properties were determined using the integrated volume method (IVM), which relies on measurements of aerosol particle concentrations at different thermodynamic equilibrium states. The measured decrease in particle concentration upon heating in a flow tube, a thermodenuder, can be correlated with saturation pressure and enthalpy of vaporization via the IVM equation, which was derived from fundamental principles, namely the Clausius-Clapeyron relation, mass conservation, and ideal gas law. The main advantage of the IVM over other methods reported in the literature is that the other methods use kinetic-based techniques to measure thermodynamic properties which requires assumptions on the usually unknown evaporation coefficient; the IVM, on the other hand, is equilibrium-based and thus requires no assumption on the evaporation coefficient. We have applied the IVM to C-4, -6, -7, and -9 dicarboxylic acid aerosols, which are pertinent to atmospheric secondary organic aerosols. Saturation pressure and enthalpy of vaporization values obtained for these compounds were respectively 3.7E-4 Pa and 88 kJ/mol, 3.4E-5 Pa and 135 kJ/mol, 7.2E-5 Pa and 149 kJ/mol, and 1.4E-5 Pa and 145 kJ/mol. </p><p>The IVM was also used to determine activity coefficients of individual compounds in binary mixtures as a function of their mole fractions. We demonstrated this method using the following four model systems. System 1: adipic acid - pimelic acid, which illustrated polar organic - polar organic interactions. Non-ideal behavior was observed with activity coefficients around three at infinite dilution. System 2: adipic acid - dioctyl sebacate, which illustrated polar organic - non-polar organic interactions. The compounds in this experiment did not form a solution. System 3: adipic acid - ammonium sulfate, which illustrates polar organic - inorganic interactions. The compounds in this experiment did not form a solution. System 4: adipic acid - ambient extracts, which illustrated the potential use of the method to study partitioning behavior of individual components in a complex matrix approximating that of real ambient aerosol. The measured activity coefficient of adipic acid was less than unity for the tested range of mixing ratios, indicating suppression of volatility of this compound in ambient organic matrix.</p><p>We have investigated three controversial issues associated with the IVM as well as other methods which utilize thermodenuders and/or aerosol generation by spray atomization and drying: 1) equilibration time scales in thermodenuders, 2) the need of an activated carbon (AC) denuder in the cooling section, and 3) the effect of residual solvent on measured thermodynamic properties of aerosols generated by spray atomization and drying. Both numerical simulations and experiments showed that the aerosols approached equilibrium within reasonable residence times (15 s - 30 s) for aerosol size distributions typical for laboratory measurements. We have also performed dimensional analysis on the problem of equilibration in TDs, and derived a dimensionless equilibration parameter which can be used to determine the residence time needed for an aerosol of given sized distribution and kinetic properties to approach equilibrium. Using both model simulations and experiments, we have shown that with aerosol size distributions relevant to both ambient and laboratory measurements re-condensation in the cooling section, with and without an AC denuder, was negligible. Thus, there is no significant benefit in using an AC denuder in the cooling section. To investigate the effect of residual solvent on measured thermodynamic properties, we compared measurements of saturation pressure and enthalpy of vaporization of C-6 (adipic) and C-9 (azelaic) dicarboxylic acid aerosols generated by atomization of aqueous solutions to those generated by homogeneous condensation using a modified Sinclair - La Mer generator. We found no statistically significant difference between the tested aerosol generation methods, indicating that residual solvent carried by the particles had no impact on the measurements.</p><p>To determine the evaporation coefficient, we developed the integrated volume - tandem differential mobility analysis (IV-TDMA) method. This thermodenuder-based method allows separate determination of the three parameters governing aerosol evaporation, namely, saturation pressure, surface free energy, and evaporation coefficient. Saturation pressure was determined using the IVM, while evaporation coefficient and surface free energy were determined by fitting particle evaporation rates measured under non-equilibrium conditions to a numerical model of the evaporation process. Evaporation coefficient was determined in a size range where surface free energy effects were negligible, allowing for single parameter optimization. We obtained evaporation coefficient and surface free energy values of 0.07 and 0.15 J/m2, 0.08 and 0.17 J/m2 and 0.24 and 0.23 J/m2 for C-4, -6, and -7 dicarboxylic acids, respectively.</p> / Dissertation

<p>Volatile organic compounds (VOCs) are a family of chemicals which are known to have adverse effects on climate change and health, and thus emissions of VOCs are regulated. One such control method is via biodegradation in a biofilter and other similar reactors. Many hydrophobic VOCs, however, are difficult to degrade in such devices. Biphasic bioreactors are designed to remove and treat hydrophobic compounds from waste gas streams. In addition to the water phase, a biphasic bioreactor includes a secondary (2°) liquid phase where hydrophobic VOCs are absorbed and made available for degradation by bacteria. A viable 2° phase is non-miscible with water, non-toxic to bacteria in the bioreactor, and has a strong affinity for target pollutants. In this work, methods were explored by which candidate 2° phases may be screened for suitability to treat two commonly studied hydrophobic VOCs, toluene and hexane. 2° phases included the commonly used silicone oil, paraffin oil and several ionic liquids (ILs), a novel type of solvent popular with the chemical industry. The air-liquid partition coefficient of toluene and hexane with each 2° phases was determined. Additionally the effect on the oxygen uptake rate (OUR) and cell growth in a flask of each 2° phase on biological cultures enriched on toluene and hexane was studied. It was determined that OUR is a poor method of screening 2° phases for biophasic bioreactors. Additionally, cell growth studies failed to capture accelerated degradation of the target pollutants in biphasic cultures. The presence of ILs resulted in significant biological inhibition, and thus do not appear to be promising 2° phase candidates for biodegradation purposes.</p> / Thesis

Cost-benefit analysis has long been a dominant method of policy analysis. When applied to policies affecting the environment, however, it faced a serious problem. Many policies exert environmental impacts that are external to market transactions, so the values of these impacts resist monetary measurement. This shortcoming in cost-benefit analysis led some researchers to develop indirect and nonmarket methods of valuing environmental goods monetarily. They include the travel cost method, hedonic pricing, and contingent valuation. The popularity of these methods has grown since their inceptions, but so have controversies over their use. Economists and others have taken all sides of the debate over the validity of the methods and their normative implications. These methods popularity and controversies necessitate their critical evaluation. This research fills this need through an extensive meta-analysis of 228 existing environmental valuation studies representing the contemporary practices in each method, and capturing varieties of environmental goods and settings. The analysis tested the convergent validity of the three valuation methods, and measured the moderating effects of select variables. The results show that effect sizes of the hedonic pricing and travel cost methods converge, but contingent valuation produces effect sizes that average 40% to 55% less than the other two methods. This difference varies significantly with the environment good being valued. Other significant moderating variables include the magnitude of the environmental change, the description of the change, and the location of the study. The year of study does not significantly moderate effect sizes. These results supplement descriptive and normative frameworks for environmental valuation described by Barbier (1994), Navrud and Pruckner (1997), and Norton (1995). When the evidence and these frameworks are considered together, the defensible uses of these three valuation methods become very limited. Valuation efforts should focus on multiple dimensions of environmental value, besides economic dimensions, that reflect ecological health and public concerns for the environment.

Statistics gathered by FEMA indicate that nine of ten federal disasters are related to flooding. Research has demonstrated that increases in flooding can be contributed to urbanization or the construction of new residential and commercial developments (Anderson, 1970; Arnold & Gibbons, 1996; Putnam, 1972). New development has two main problems associated with it. First is the increase in impervious surfaces due to new parking lots, buildings, and streets (Booth & Leavitt, 1999; Seaburn, 1969). Second is the elimination of natural vegetation, which reduces evapotranspiration and lowers the soils ability to absorb precipitation (Hewlett, 1982). This study first demonstrates the relationship between land use and land cover characteristics associated with urbanization to hydrograph statistics, specifically time to rise and total rise. Secondly to create predictive models of watershed behavior based on these measures. Time to rise is the time between the inception of a storm and the initial rise of stream stage. Total rise is the total rise in stage to its peak, during the entire storm. This study represents a new geospatial approach for studying these relationships. The study first established a GIS database of land use and land cover characteristics. The second phase performed regression analyses of the hydrograph response variables with the land use and land cover characteristics as independent variables. There were statistically significant relationships between residential development, commercial development and roads with the response variables, time to rise and total rise. As development increases time to rise decreased and total rise increased. The percentage of forest land use, land maintained as contiguous forest, was correlated with total rise. As the percentage of forest land use increased the total rise decreased. This study demonstrates some univariate models that show direct relationships between land use and land cover characteristic and hydrograph response.

Drilling fluids and muds are an essential component of the rotary drilling process used to drill for oil and gas on land and in offshore environments. However, the bioaccumulation of petroleum contaminated soils/drilling mud due to oil and natural gas exploration has posed a major environmental concern due to its prolonged environmental persistence and its leachability below the rhizosphere. The main objectives of this research were: (i) To assess initial toxicity of drilling mud and related contaminated soils from an agricultural setting in Galliano, Sicily (Phase one) and (ii) To develop a low intervention bioremediation approach using bioplug technology to ensure that the soil/drilling mud has met U.S. and international soil/ground water quality standards by performing a microcosm study (Phase two). Total petroleum hydrocarbon content of the drilling mud reduced to 617.0±176.0, 446.0±195.0, and 533.0±138.0 mg/kg from 5000.0±530.0 mg/kg after treatment via mixing (84.2-95% reduction). The PAH and phenol concentration of the drilling mud resulted in a 97-99.5% reduction via mixing (5d study) and 69.4-77.9% reduction via in situ treatment (40d study). The metals of concern for the drilling mud are cadmium and selenium. Both metals had exceeded Italian and La DEQ soil leachability standards, which were established at 0.005 mg/L for cadmium and 0.010 and 0.050 mg/L for selenium, respectively. In situ bioremediation was performed on a cross-section of Italian soil/mud to test the effectiveness of bioplug technology. Total petroleum hydrocarbons had reduced from 217.12±43.38 and 149.68±45.51 mg/kg to 15.16±3.35 and 34.27±15.86 mg/kg for the control drilling mud test beds, and from 89.20±67.42, 141.71±64.80, and 197.87±77.38 mg/kg to 5.24±6.15, 15.02±10.20, and 9.65±9.37 mg/kg for the experimental drilling mud test beds, respectively. The efficiency of degradation for control and experimental setups were 85.1±11.2% and 92.9±3.0%, respectively. Overall, the microcosm experiment indicated that a significant reduction in total petroleum hydrocarbons had taken place for the drilling mud using bioplug technology and will be installed at the Italian site.

Governmental agencies have set regulatory values on the concentration of dye-related color that can be released in textile mill effluents. A proprietary biotic and abiotic technology treatment train was built at a candidate facility in northwestern Georgia to reduce the organic content and dye-related color content in the textile mills effluent. Laboratory experimentation began with bench scale 4 L immobilized microbe (IMBR) bioreactor tests to biologically treat primary wastewater streams, namely skein dye and space dye, from this candidate facility. The biological treatment reduced the organic content levels, expressed as chemical oxygen demand (COD), from 3185±30 to 290±20 mg/L (COD reduction rate: 43.21±0.1 mg/L/h) in the skein dyeing effluent and from 5430±30 to 550±120 mg/L (COD reduction rate: 72.8 ± 1.3 mg/L/h) in the space dyeing effluent; however, the biological process did not remove all of the color from the effluent sample. An ozonation unit was added to the biological treatment process to aid in color reduction. The ozonation successfully reduced the residual color in both primary effluent streams. The skein dyeing effluent was reduced from 4.9 to 0.3 mg/L of residual color (color removal rate: 0.069 mg/L/h). The space dyeing effluent was reduced from 16.0 to 1.5 mg/L of residual color (color reduction rate: 0.21 mg/L/h). Both organic content and color removal exhibited >89% reductions. However, to produce water devoid of color from the effluent samples, activated carbon was added and filtered out to further clarify the ozone treated water. The resultant water was of recyclable quality. These laboratory processes were then adapted to create a commercial scale technology treatment train at the candidate facility. The commercial unit, operating at 110 gpm (gallons per minute) with a system hydraulic retention time of 41.6 hours, had reduction levels of >78% for both organic content reduction and color removal. These levels were acceptable treatment levels with the resultant effluent successfully recycled into the dye house processes. Thus, recyclable process water was produced from the effluent waters of the candidate textile mill facility.

Wildland fires are part of the United States history and culture. The human dimension of State wildland fire management, - the relationship of people and wildland fire in America- is an important and driving force in how federal and state agencies respond to wildland fire, now and in the future. In many ways, the critical element for the management of wildland fire is the management of people, communities, and organizations. Explosive growth in the wildland-urban interface puts entire communities, their associated infrastructure and the socioeconomic fabric that holds communities together at a high risk from wildland fire. Year after year fires are getting worst. The risk now is even bigger since more people live in the wildland-urban interface. The 2000 fire season highlighted the vulnerabilities of these wildland-urban interface communities, including industries, businesses, occupational groups, families, and individual citizens. This research attempts to determine the influences on state-level policies for wildfire risk reduction in the wildland-urban interface. All fifty States were selected to be studied in terms of their policies on wildfire risk reduction. Data was collected from the States in a survey form, and then analyzed to determine what factors may influence the states wildfire risk reduction polices. This research is an important first step in understanding the choices, approaches and specific activities undertaken by state decision-makers facing unprecedented threats from catastrophic wildland fire.

Recycling consists of diverting or recovering materials from the solid waste stream that would otherwise end up returning to the environment as a potential source of pollution. These collected materials are then used as raw materials in the manufacture or assembly of a new product or package. Over the years the amount of municipal solid waste being generated per person has steadily increased. Waste disposal costs are also increasing, making recycling even more important. To address this issue cities are developing recycling policies or plans. The type of plan varies according to the area; as of this time there are no national recycling standards or legislation being imposed. The Environmental Protection Agency is currently encouraging state and local governments to adopt a recycling program to reduce the amount of municipal solid waste being sent to landfills and incinerators. This study attempts to determine the types of municipal recycling programs and the success of those programs (measured by the participation rate) that have been instituted by cities. State capitals were selected as the cities to be studied in terms of their recycling programs and participation rates. Data was collected from these cities in both survey form and through the United States Census Bureau and 1991-1992 Green Index. It was then analyzed to determine what factors, if any, are associated with participation in the recycling programs in these cities. Significant correlations were found between participation and median value of owned homes, percent renter occupied housing units, percent bachelors degree or higher, and main type of recycling program. The municipal solid waste fee policy variable was not found to be significant but was determined to still be relevant to the study due to previous research and a significance level below .10.

Since 1987, the concept of sustainable development, which tries to combine economic, social and environmental concerns into one benign development model, has become increasingly popular worldwide. To explore and explain the differences in accomplishing sustainable development, this thesis looks at one specific aspect: the energy sectors in the United States and the European Union. After giving an overview on the political and theoretical aspects of sustainable development, the various sustainability dimensions in the energy sector are explored. The following four reasons which warrant the change of the current fossil fuel intense energy sector are discussed: first, air pollution; second, insecurity of energy supplies; third, ultimate exhaustion of fossil fuels; and finally, climate change. Following the development of the methodology, various statistical tests are performed using a variety of indicators. Using Wilcoxon?s rank sum test significant differences between the U.S. and the EU energy sectors are discovered in energy intensity, carbon dioxide emissions, as well as per capita energy consumption in the various energy end-use sectors. Afterwards, a Sustainable Energy Index (SEI) is developed identifying Austria, Sweden and Finland as having the most sustainable and Wyoming, Alaska and West Virginia as having the least sustainable energy sectors. In addition, through regression analysis, energy intensity, share of renewables and energy consumption in the transportation sector are determined to have the greatest impact on carbon dioxide emissions. After the discussion of the SEI policy recommendations are developed, whose prompt implementation is desirable given the global rise in energy consumption and the negative consequences of climate change. Finally, a conclusion is drawn that no country or state has yet achieved a sustainable energy sector. Nonetheless, it was observed that, in general, European Countries scored better than American States, which can be attributed to better energy and environmental policies.

Triazine herbicides are the most heavily used pesticides in the United States. Atrazine and Simazine are the primary triazine herbicides used for broadleaf weed control in the production of corn, sugarcane, and sorghum. Recent monitoring studies of surface waters in the Upper Terrebonne Basin of Louisiana indicate elevated amounts of triazines are running off fields and entering drinking water supplies. Atrazine has been classified as a possible carcinogen by the United States Environmental Protection Agency. Recent epidemiological studies have revealed increases in breast cancer and pre-term births following exposure to triazines at levels detected in drinking water. Non-point source pollution is a major problem affecting the water quality in the United States. Agriculture contributes a large percentage of non-point source water pollution, with sediment, pesticides and animal waste transported into waterways with surface runoff. Recent amendments to the Clean Water Act require that States identify impaired waters and develop Total Maximum Daily Load Budgets for these waters. Best Management Practices have been advocated as a method to reduce non-point pollution to meet these new regulations. Data were collected in the Upper Terrebonne Basin of Louisiana before and after the farmers were advised to follow Best Management Practices to reduce Atrazine runoff . Samples of finished and raw water were collected from Iberville Water District Three and analyzed for atrazine concentration by the Louisiana Department of Agriculture and Forestry. Atrazine concentration data were evaluated using Dynamic Linear Models, with stream flow from Bayou Grosse Tete as a regressor. This analysis revealed that stream flow has a significant influence and accounts for most of the change in atrazine concentrations at the Iberville water facility. The trend in acreage of crops planted in the UTB had a decrease in the number of crop acres that could utilize Atrazine. The sale of Atrazine in the UTB also increased for the years at the beginning and end of this study. From the results of the time series analysis, it appears that Best Management Practices had less effect than stream flow on Atrazine concentrations at Iberville Water District Three.