Browsing by Subject "Contamination"
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Item Open Access An Examination of PFAS for North Carolina Policymakers and Researchers(2021-04-30) Kluck, Johanna; Nocera, Karly; Zhang, QixuanThis Master’s Project aims to explore factors impacting the occurrence, distribution, toxicology and remediation of PFAS – a type of emerging contaminant – in North Carolina’s water. Research methods utilized include a literature review, interviews, and quantitative data analysis of Department of Environmental Quality’s water quality samples. Due to a lack of publicly available information and regulatory oversight, many PFAS-related concerns – such as identifying individual households at risk – are unable to be effectively addressed in the scope of this project. The team sought to synthesize existing knowledge and identify gaps in order to inform both the academic community’s future research and upcoming policy efforts. To better connect and communicate ongoing research with non-academic communities, as well as identify areas of PFAS knowledge that need further investigation, our final product involves multiple deliverables: (1) a scientific paper with an extensive literature review, and (2) an ESRI StoryMap conveying our findings and synthesis in a publicly accessible format and language.Item Open Access Assessing the well water quality in a rural Georgia county: Do Washington County citizens need to worry?(2008-08-27T02:58:24Z) Hitchcock, KristenUnder the Safe Drinking Water Act, public water sources must be monitored for contaminants; and the results are made public. However, this Act does not cover private wells, leaving a significant portion of the population unprotected. In one rural Georgia county, Washington, an estimated 3,997 wells are currently in use. Local health officials believe that well contamination is a problem for the people using these wells. The purpose of this project was to take the available data and briefly assess the state-of-affairs for the county. After researching topics unique to Washington County and determining potential sources of well water contamination, aluminum, silica, manganese, total and fecal coliform bacteria, pH, and hardness were chosen for assessment. Despite limitations in the data, this study filled an important knowledge gap for Washington County in that no analysis had been conducted of the available data. For the parameters tested, it was concluded that Washington County well owners were not facing a significant health threat. Additionally, differences in contaminant levels among soil type and year of sample were not significant. The most important problem currently facing the county is lack of data. Washington County must begin to test wells more frequently to better assess contaminants of concern and to focus education and remediation efforts.Item Open Access BASELINE GROUNDWATER QUALITY TESTING NEEDS IN THE EAGLE FORD SHALE REGION(2012-04-27) Palacios, Virginia E.As the pace of drilling in the Eagle Ford shale increases, so does the potential for groundwater contamination incidents. The goals of this analysis are (1) to determine whether existing baseline groundwater quality data in the Eagle Ford shale region is adequate to provide a comparison to potential future contamination from oil and gas development and (2) to define an appropriate and cost-effective list of parameters that will aid in strategic planning of baseline ground water quality testing in the Eagle Ford shale region for the same goal. First, a list of potential testing parameters is defined using case studies of proposed groundwater contamination. Second, formation water chemistry in the Eagle Ford shale region is compared to groundwater chemistry in the counties of the Eagle Ford shale region to determine which chemical indicators demonstrate potential to consistently detect contamination. Third, statistical power analysis is used as a guideline to decide whether more samples are needed for each testing parameter in each county in the Eagle Ford shale region. Next, known health effects of each testing parameter are described in order to highlight potential pollutants that should be prioritized in a sampling initiative. Finally, testing costs are reported to introduce a perspective about microeconomic choices affecting which stakeholders take responsibility for baseline groundwater quality testing. These tasks led to the findings that some of the most dangerous potential pollutants, including methane, total petroleum hydrocarbons, nitrate, volatile organic compounds, polycyclic aromatic hydrocarbons, alpha particles, beta particles, and gamma radiation, are poorly characterized in the region, if at all. Furthermore, testing these parameters is more expensive than testing less hazardous ones. Water well owners may be unable to afford the expense of testing these parameters. Therefore, a testing initiative facilitated by agencies, industry, or other organizations may be more efficient at establishing a regional baseline for these high priority, expensive tests. As such, the framework and analysis presented here can be used by groundwater managers in the Eagle Ford shale region to develop baseline sampling strategies tailored to specific counties in the region.Item Open Access Contamination by the Israeli Military Industry and its Impact on Apartment Sale Prices in an Adjacent Tel-Aviv Neighborhood: A Hedonic Pricing Model Study(2008-04-23T15:48:25Z) Shelem, ItaiA window of opportunity opened to investigate present effects of past environmental policies of the Israel Defense Forces and its military industry when one of its facilities, Taas Magen, was required to close down in 1997. For decades, untreated discharge was released into absorption pits, which contaminated the soil and groundwater with many toxic compounds, including the carcinogen trichloroethylene. Surrounding the industrial facility is a housing market, consisting of more than 11,000 apartments, directly affected by the contamination. This hedonic pricing model study quantifies the effect of the environmental degradation due to the operations of Taas Magen on the nearby housing market. This was achieved by examining the effect distance away from Taas had on apartment sale prices. Results show that apartments near the facility were more negatively impacted than those further away. Next, the model was expanded to isolate the impact of the contamination from that of the facility by incorporating information regarding the public’s awareness of the degradation. The resulting regression coefficients suggest that only after public acknowledgement of the harm did distance significantly impact prices. Therefore, it is the environmental contamination and not necessarily the facility that negatively impacted prices. As a result of the contamination, the mean apartment price loss was -$24,650.74 (’06 dollars), which is approximately 14% of an apartment’s average value. Losses to the surrounding housing market are estimated at $267 to $287 million. These are only a minimum of the total social and economic costs incurred by the greater community, which are estimated to total at least $358 million. Assuming the government were to fund the estimated $33 million cleanup costs, a minute gain of 1.5% in the value of this $2.2 billion housing market would create the necessary economic benefit to offset the cost of decontaminating the site. Similarly, a more technologically advanced, yet expensive, iron nanoparticle remediation process would require a gain of 10.1% to offset its costs. Such market gains are not unreasonable given a drastic decrease in environmental harms. Furthermore, reclaiming a lost aquifer, reduction in human health risks, restoration of environmental integrity, and further increases to the housing market are all benefits of remediation that may greatly overshadow the concomitant cleanup costs. Future research should focus on quantifying all these benefits. With such information at hand, it will undoubtedly become apparent that remediation is socially and economically feasible.Item Open Access Geochemical and Isotopic Characterization of Coal Combustion Residuals: Implications for Potential Environmental Impacts(2012) Ruhl, LauraCoal fired power plants are ubiquitous in the United States and most developed countries around the world, providing affordable electricity to consumers. In the US, approximately six hundred power plants generate 136 million tons of Coal Combustion Residuals (CCRs) annually, encompassing fly ash, bottom ash, and flue gas desulfurization materials. The range and blends of CCRs varies substantially across coal-fired plants and depends on a unique set of circumstances for each plant and coal source. Current U.S. regulations mandate the installation of advanced capture technologies to reduce atmospheric pollution, but do not address the transfer and storage, or the potential impacts to water resources. Thus improved air quality is traded for significant enrichments of contaminants in the solid waste and effluent discharged from power plants.
This work examines the geochemical and isotopic characteristics of CCRs, as well as potential environmental impacts from CCRs. This investigation looks at several different aspects of CCR and environmental interactions from 1) the immediate impacts of the 2008 TVA coal ash spill in Kingston, TN, 2) the long-term (18-month) exposure of the spilled ash in the Emory and Clinch rivers, 3) impacts on waterways in North Carolina that receive CCR effluent from coal fired power plants, and 4) examination of boron and strontium isotopes of CCRs from leaching experiments and their application as tracers in the environment of the TVA spill and NC waterways. These investigations have illuminated several conclusions, including contact of surface water with CCRs leach high concentrations of leachable CCR contaminants, such as As, Se, B, Sr, Mo, and V in the surface waters; the dilution effect is critical in determining the concentration of contaminants from the CCRs in surface water (both at the spill and in waterways receiving CCR effluent); recycling of trace elements (such as As) through adsorption/desorption can impact water quality; and elevated boron and strontium concentrations, in addition to their isotopes, can trace CCR effluent in the environment. Combining the geochemical behavior and isotopic characteristics provides a novel tool for the identification CCR effluents in the environment.
Item Open Access Identifying water contamination from fossil fuel development using geochemical and isotopic fingerprints(2017) Harkness, JenniferFossil fuels continue to be a major component of the energy economies in North America, accounting for 60% of electricity generation in the U.S. Recent incidences (i.e. spills) and limited regulation of the fossil fuel industry has generated public concern about the risks fossil fuel development pose to water resources. Previous studies have identified negative impacts on water quality associated with the storage and disposal of coal combustion residuals, oil sands process-affected water, and oil and gas wastewater, as well as leaking of methane to groundwater in areas of hydraulic fracturing. In addition, contamination of water resources from natural (geogenic) sources has also been observed in many of the areas associated with fossil fuel development. Since naturally occurring saline water is common in some regions associated with fossil fuel explorations, delineating the effects of anthropogenic contamination sources is a major challenge for evaluating the impact of fossil fuel development on water quality.
This thesis investigates the geochemical and isotopic characteristics of wastewater from coal combustion residual storage ponds, unconventional oil and gas exploration, and oil sands mining, in an attempt to evaluate the use of geochemical and isotopic tracers to identify fossil fuel-associated wastewaters in the environment. This includes the investigation of (1) halogen (Br, I) and ammonium contents of oil and gas wastewater (OGW);(2) the lithium isotope ratios in OGW and coal combustion residuals; and (3) the inorganic geochemistry and boron, strontium and lithium isotope ratios of oil sands processed-affected water (OSPW). In three case studies, these geochemical and isotopic tools were integrated into comprehensive geochemical frameworks that investigated the (1) leaking of coal ash ponds to surface and groundwater in the southeastern United Sates; (2) geochemistry of groundwater in an area of shale gas development in West Virginia through time and space; and (3) evaluation of the sources of molybdenum in contaminated groundwater in southeastern
Wisconsin and possible links to coal ash surface disposal. These investigations illustrate a range of situations in which isotopic fingerprinting provided a unique geochemical tool that can successfully identify fossil fuel-related wastewater in the environment. These studies have also demonstrated the environmental impact upon releasing of fossil fuels wastewater to the environment. The case studies support the use of geochemical and isotope tools as robust methods to not only identify contamination of water resources by fossil fuel-related activities, but also to distinguish wastewater contamination from naturally occurring contamination in areas of fossil fuel development. These studies highlight the benefit of using a suite of geochemical tools when investigating water quality impacts.
Item Open Access Legacies of Lead Paint Contamination in the Mineral Soils Adjacent to Historic Buildings(2023-04-28)For hundreds of years, compounds containing the element lead (Pb) have been added to paint in order to improve the texture and weather resistance. Across the United States, millions of homes and buildings were painted with lead-based paints up through the 1970s, when lead paint was phased out following medical research confirming the link between lead and a variety of neurological and developmental disorders. Over 170 million Americans are estimated to have been exposed to lead levels above safe concentrations, many of whom were likely exposed to soil lead while playing in yards as children. Although the phase-out of lead in paint began over 50 years ago, the legacies of contamination from lead paint are still present in the soil in a meaningful way. This is largely due to the immobile nature of lead in the soil, tightly binding to clays and other particles, preventing it from being leached out of the soil. Previous soil lead studies have attempted to characterize spatial patterns of contamination at various scales, but this study is unique in the highly fine-scale sampling design around each structure. Up to 190 samples were taken around each structure, at a point density of 1 sample every 4-12 square meters, prioritizing areas closer to the base of the structure. Nine study sites were chosen in the vicinity of Durham, North Carolina, including 2 buildings that continue to be well-maintained, 5 dilapidated structures, and 2 footprints of buildings burned to the ground. For our study, we surveyed the top inch of the mineral soil using an Olympus Vanta portable X-ray Fluorescence Machine to get lead concentration in parts per million. At all nine of our study sites, we found evidence of elevated lead levels in the mineral soil that can reasonably be attributed to legacies of paint contamination. Sites varied in the intensity of lead contamination, ranging from maximum values below 300ppm to multiple samples above 5000ppm, and each had its own unique footprint of soil lead. Interpolations of lead concentration were created in ArcGIS from the point data. Despite the variation, we were able to draw a variety of conclusions about the state of soil lead around historic structures: • Concentrations are typically highest adjacent to the base of the structure, and often decline rapidly with distance. • Concentrations often decline back down to the geologic background within 4-12 meters of the structure, related to the maximum concentration. • The corners of buildings are often hotspots for lead contamination, likely due to weathering patterns of paint. • Topography and erosion of soil can affect concentrations and directionality of elevated lead plumes. • We did not find any direct pattern between lead levels and a building’s height, age, location, or level of maintenance. • Destroyed/burned structures can show very high hotspots even within the footprint of the former structure. • Mulch and other ground covers may either protect the soil from contamination or insulate the soil lead from loss. Statistical and geospatial analysis was used to help characterize the spatial patterns of the contamination at each site. For each structure, data of lead concentration versus distance from the building was used to generate a logarithmic regression that can be used to predict concentration at any given distance. For two structures, interpolations were georeferenced to estimate the area of spatial contamination at different thresholds. Other analyses were done on a site-specific basis, such as comparing concentrations at the different cardinal directions from one structure. All of our results were communicated and interpreted to the landowners to help inform their knowledge of their properties. This is especially important considering most of our sites are open to the public, and multiple have outdoor programs for children. For each site, we estimated a total health risk, based on the levels of lead contamination and the potential for human exposure. Considering the levels still present in soils even after 50+ years, more research is needed into soil remediation methods, as the high values we found in soils demonstrate that lead still poses a considerable risk to humans.Item Open Access Legacies of Lead Paint Contamination in the Mineral Soils Adjacent to Historic Buildings(2023-04-28) Skinner, Adam; Lambert, CarsonFor hundreds of years, compounds containing the element lead (Pb) have been added to paint in order to improve the texture and weather resistance. Across the United States, millions of homes and buildings were painted with lead-based paints up through the 1970s, when lead paint was phased out following medical research confirming the link between lead and a variety of neurological and developmental disorders. Over 170 million Americans are estimated to have been exposed to lead levels above safe concentrations, many of whom were likely exposed to soil lead while playing in yards as children. Although the phase-out of lead in paint began over 50 years ago, the legacies of contamination from lead paint are still present in the soil in a meaningful way. This is largely due to the immobile nature of lead in the soil, tightly binding to clays and other particles, preventing it from being leached out of the soil. Previous soil lead studies have attempted to characterize spatial patterns of contamination at various scales, but this study is unique in the highly fine-scale sampling design around each structure. Up to 190 samples were taken around each structure, at a point density of 1 sample every 4-12 square meters, prioritizing areas closer to the base of the structure. Nine study sites were chosen in the vicinity of Durham, North Carolina, including 2 buildings that continue to be well-maintained, 5 dilapidated structures, and 2 footprints of buildings burned to the ground. For our study, we surveyed the top inch of the mineral soil using an Olympus Vanta portable X-ray Fluorescence Machine to get lead concentration in parts per million. At all nine of our study sites, we found evidence of elevated lead levels in the mineral soil that can reasonably be attributed to legacies of paint contamination. Sites varied in the intensity of lead contamination, ranging from maximum values below 300ppm to multiple samples above 5000ppm, and each had its own unique footprint of soil lead. Interpolations of lead concentration were created in ArcGIS from the point data. Despite the variation, we were able to draw a variety of conclusions about the state of soil lead around historic structures: • Concentrations are typically highest adjacent to the base of the structure, and often decline rapidly with distance. • Concentrations often decline back down to the geologic background within 4-12 meters of the structure, related to the maximum concentration. • The corners of buildings are often hotspots for lead contamination, likely due to weathering patterns of paint. • Topography and erosion of soil can affect concentrations and directionality of elevated lead plumes. • We did not find any direct pattern between lead levels and a building’s height, age, location, or level of maintenance. • Destroyed/burned structures can show very high hotspots even within the footprint of the former structure. • Mulch and other ground covers may either protect the soil from contamination or insulate the soil lead from loss. Statistical and geospatial analysis was used to help characterize the spatial patterns of the contamination at each site. For each structure, data of lead concentration versus distance from the building was used to generate a logarithmic regression that can be used to predict concentration at any given distance. For two structures, interpolations were georeferenced to estimate the area of spatial contamination at different thresholds. Other analyses were done on a site-specific basis, such as comparing concentrations at the different cardinal directions from one structure. All of our results were communicated and interpreted to the landowners to help inform their knowledge of their properties. This is especially important considering most of our sites are open to the public, and multiple have outdoor programs for children. For each site, we estimated a total health risk, based on the levels of lead contamination and the potential for human exposure. Considering the levels still present in soils even after 50+ years, more research is needed into soil remediation methods, as the high values we found in soils demonstrate that lead still poses a considerable risk to humans.