Master of Environmental Assessment Professional Papers

Permanent URI for this collectionhttps://www.lib.ncsu.edu/resolver/1840.20/16

Browse

Now showing 1 - 20 of 123

1,4-Dioxane and the Application of Phytoremediation at North Carolina Hazardous Waste Groundwater Contaminated Sites
(2013-11) Sorensen, Heather
Abstract Sorensen, Heather. Master of Environmental Assessment. 1,4‐Dioxane and the Application of Phytoremediation at North Carolina Hazardous Waste Groundwater Contaminated Sites 1,4‐Dioxane is a manufactured chemical that is considered to be recalcitrant in nature due to its inability to be remediated through traditional groundwater remediation systems and its inability to degrade under ambient groundwater conditions. 1,4‐Dioxane has been established as “likely to be carcinogenic to humans by all routes of exposure” by the United States Environmental Protection Agency. Through historical releases and improper disposal of industrial waste and accidental spills of 1,4‐dioxane chemicals to the environment, groundwater has become contaminated with 1,4‐dioxane. The goal of this paper is to identify Treatment Storage and Disposal Facilities in North Carolina with 1,4‐ dioxane contaminated groundwater and evaluate the potential application of phytoremediation as a viable remedial option for 1,4‐dioxane. Through the investigation of 1,4‐dioxane and phytoremediation, this paper explores why 1,4‐dixoane is a constituent of concern and why phytoremediation should be considered as an remediation strategy for contaminated groundwater. Twelve 1,4‐dioxane hazardous waste sites with 1,4‐dioxane contaminated groundwater were provided by the North Carolina Department of Environment and Natural Resources, Division of Waste Management, Hazardous Waste Section. Six out of the twelve sites were assessed for phytoremediation applicability. This assessment demonstrates that phytoremediation should be considered as a viable remedial option for 1,4‐dioxane, specifically at sites that have no current remediation strategy and that have access to space for a phytoremediation tree stand.
A Case Study of Human Health Hazards and Environmental Effects Associated with the Release and Exposure of Arsenic Compounds from Poultry Litter Incineration
(2013-07) Roston, Jeremy
ABSTRACT ROSTON, JEREMY B. Master of Environmental Assessment. A Case Study of Human Health Hazards and Environmental Effects Associated with the Release and Exposure of Arsenic Compounds from Poultry Litter Incineration. Arsenic, particularly Roxarsone (3-nitro-4-hydroxy benzene arsonic acid), is a common feed additive widely used by the poultry industry that acts as a highly effective growth promoter by controlling coccidiosis, a parasitic intestinal disease. A growing body of research and literature has revealed that organic arsenicals used in poultry feed, such as Roxarsone, are converted to inorganic arsenicals within the chicken and are also rapidly transformed into inorganic arsenic in poultry wastes and in soils. Based on sufficient evidence of carcinogenicity in humans, Arsenic and inorganic arsenic compounds are known to be human carcinogens. Epidemiological studies have demonstrated that inorganic arsenic compounds increase the risk of cancer in the skin, lung, digestive tract, liver, urinary bladder, kidney, and lymphatic and hematopoietic systems. Although the impacts of Roxarsone on human health and the environment are still unknown, studies have found that all these biological effects require the metabolism of organoarsenical compounds to the more highly toxic inorganic Arsenic (AsIII, AsV) species. This is of great concern in regions of the US where the landscape is dominated by poultry Concentrated Animal Feeding Operations (CAFOs). In North Carolina alone, 787 million broilers are produced on an annual basis, and with it, an estimated 6.1 million tons of poultry manure is generated and land applied on agricultural lands. Utilization of animal manure as an organic fertilizer on private farm land is still the prefer means of waste management and disposal. However, obtaining renewable energy through the incineration of poultry litter has been proposed as an alternative by the North Carolina state legislature when it passed Session Law 2007-397. Nonetheless, despite continue urban expansion into rural areas, land use change, decline in water quality standards, and elevated nutrient in soils amended by poultry litter, it is necessary to carefully evaluate poultry litter incineration as a means for an alternative to waste management disposal, and its impacts on human health and the environment. Through the examination of current published information on the subject, this case study evaluates research related to human health hazards and the potential environmental effects associated with the exposure and release of arsenical compounds when poultry litter is incinerated. This paper also gathers and examines any relevant peer-reviewed research that provides sufficient evidence to further educate the public about the potential effects of poultry litter incineration and its feasibility as a renewable energy alternative for North Carolina.
A Case Study: Emergency Response and Time Critical Removal Action for the Stony Hill Road Trichloroethylene (TCE) Site in Wake Forest, NC
(2013-05) Rhame, Kenneth
RHAME, KENNETH. Emergency Response, Removal Site Evaluation and Time Critical Removal Action for the Stony Hill Road TCE Site in Wake Forest, NC. A Case Study and Review of Actions Taken; under the Authority of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA); commonly known as Superfund. (Under the direction of Linda Taylor). TCE is a volatile organic compound (VOC) that is commonly used as an industrial solvent to remove grease from metal parts. It is also found in adhesives, paint removers, rug-cleaning fluids, spot removers, etc. (USEPA TEACH TCE). TCE is present in at least 852 of the 1,430 National Priority List sites identified by USEPA (ATSDR TCE ToxFAQs). The presence of TCE at the Stony Hill Road site is believed to be attributed to improper handling/disposal related to circuit board cleaning operations. The Stony Hill Road TCE site is not currently on the NPL. TCE is a designated hazardous substance as defined by 40 CFR 302.4 The United States Environmental Protection Agency (USEPA) classified TCE as a carcinogen to humans by all routes of exposure and determined it harmful to fetal development in 2011. It is these types of compounds that threaten public health and/or the environment that allow USEPA to initiate an action under CERCLA authority. CERCLA, also known as Superfund was enacted by Congress in 1980. Superfund created a tax on chemical and petroleum industries to establish a trust that could be used to address releases or threatened releases of hazardous substances that endanger public health or the environment. The appropriation for Superfund has expired and now most funding comes from either general tax revenues or by USEPA’s cost recovery efforts against responsible parties. Therefore the funding that is available to address environmental threats from year to year will vary and likely decline due primarily to the poor economic climate. It will become necessary to utilize critical thinking in decisions being made and to utilize outside resources effectively when response actions are initiated in the future. There are two types of response actions under CERCLA: 1. Removal Actions – short term actions taken that require a immediate or prompt response to address releases of hazardous substances 2. Remedial Actions – long term actions dealing with National Priority List (NPL) sites that significantly reduce the threats associated with releases of hazardous substances, but not immediately life threatening. The National Contingency Plan (NCP) provides policy and guidance necessary in responding to releases or threatened releases of hazardous substances. The NCP is the federal government’s doctrine for environmental emergency response actions. The NCP establishes three types of removal actions; emergency response, time-critical removals and non time-critical removals. The Stony Hill Road TCE site was addressed under CERCLA, consistent with the NCP and using both emergency response and time-critical removal action authority by the Federal On-Scene Coordinator (FOSC). In order for a site to meet the criteria to be addressed by the removal program, a concentration above a removal management level (RML) formerly known as the removal action level (RAL) must be documented. The RML for TCE was recently lowered from 128 parts per billion (ppb) to 8 ppb (USEPA, 1988 and USEPA RML Table 2012). The Stony Hill Road TCE site met the criteria as the TCE concentrations present in residential wells were documented as high as 340 ppb. A review of the decisions and actions taken at the Stony Hill Road TCE site as well as issues encountered and future recommendations in responding to exposures or threats of exposures resulting from hazardous substances affecting residential drinking water wells using CERCLA authority will be presented.
A Comparison and Contrast of Environmental Monitoring Techniques from 2008 to 2014 on the Pacific Harbor Seal and Northern Channel Island Pinnipeds
(2015-05) Ortt, Jesse
Ortt, Jesse. Master of Environmental Assessment. A Comparison and Contrast of Environmental Monitoring Techniques from 2008 to 2014 on the Pacific Harbor Seal and Northern Channel Island Pinnipeds. During certain times of the calendar year, United States Spacelift launches from Vandenberg Air Force Base, California can cause stress and impact on the breeding grounds of the Pacific Harbor Seal and the Northern Channel Island Pinnipeds. The US Fish and Wildlife Service and NOAA Fisheries Service have established monitoring requirements for space lift operations from Vandenberg Air Force Base for anthropogenic noise based off of the sonic boom modeling program (PCBoom3). Following the analysis of 5 years of cumulative data of the Atlas V launches, the Air Force proposed a set of mitigation and monitoring measures that would lessen the impact on the marine mammals. This included implementing seasonal restrictions such as “avoiding missile and rocket launches during the harbor seal pupping season of March through June, whenever possible and avoiding, whenever possible, launches which are predicted to produce a sonic boom on the Northern Channel Islands during Pinniped pupping seasons” (NOAA 2013). Based on these seasonal restrictions, the requirements for monitoring were reduced for Vandenberg Air Force Base.
A GIS Database of North Carolina Municipal Waste Land Application Sites: Current Uses and Potential for Biofuels Crop Production
(2011-10) Nielsen, Laurie
ABSTRACT NIELSEN, LAURIE EVANS. A GIS Database of North Carolina Municipal Waste Land Application Sites: Current Uses and Potential for Biofuels Crop Production. (Under the direction of Dr. Elizabeth Nichols.) A Geographic Information System (GIS) database of North Carolina municipal wastewater and biosolids land application sites was developed to provide spatial information about municipal waste management lands, and to help assess the potential for production of biofuels crops on public lands within the state. The primary purpose of this database is to support ongoing research on the potential use of municipal waste land application fields for the production of biofuels crops, by providing data on the size, location, distribution and current uses of municipal liability lands in North Carolina. In addition, the database contains updated contact information for local operators and decision-makers, which will facilitate dissemination of information about biofuel crop production to the regulated community. Parties who may find the spatial database and maps useful include representatives from the Biofuels Center of North Carolina, the N.C. Department of Environment and Natural Resources (NCDENR), the N.C. Eastern Region Military Growth Task Force, the North Carolina Cooperative Extension Service, North Carolina municipalities, and others with a vested interest in the development of sustainable, renewable energy sources for the state. Maps depicting municipal facilities with non-discharge permits issued by NCDENR’s Aquifer Protection Section were created to show the state-wide distribution of sites receiving either treated wastewater irrigation or land-application of wastewater-treatment residual biosolids. A total of 90,554 acres are currently permitted to receive treated municipal wastewater products in North Carolina. Phone surveys were conducted to obtain current information about land-use patterns on these application sites, including the growing of traditional small-grain row-crops for livestock consumption, grasses used for hay or pasture, or trees. With few exceptions, virtually no biofuels crops are being produced on municipal liability lands at this time. This database represents the first known spatial depiction of total North Carolina acreage devoted to the disposal of wastewater treatment plant residues or post-treatment water. The database currently is housed on a server within the NCSU College of Natural Resources, Department of Forestry and Environmental Resources.
A human health risk assessment of exposure to polycyclic aromatic hydrocarbons (PAHs) in coal-tar sealcoats
(2012-12) Mocka, Corey
ABSTRACT MOCKA, COREY ADAM. A human health risk assessment of exposure to polycyclic aromatic hydrocarbons (PAHs) in coal-tar sealcoats. (Under the direction of Dr. Stephen Graham and Ms. Linda Taylor). Polycyclic aromatic hydrocarbons (PAHs) are organic molecules that consist of two or more fused benzene rings. They are natural components of coal or petroleum products and also formed by the incomplete combustion of organic matter, making them ubiquitous environmental contaminants. The United States Environmental Protection Agency (EPA) currently classifies seven PAHs as B2 chemicals (probable human carcinogens) and, considering their presence in most environmental exposure media (e.g., soil, sediment, water, air) PAHs are a significant concern to environmental and human health professionals. Coal-tar sealcoats are black, shiny coatings that are adhered to driveway and parking lots to increase pavement life and improve aesthetics. Recent studies by the United States Geological Survey (USGS) have determined that certain PAH concentrations in settled dust on the coal-tar seal coated parking lots were 5,300 times greater than concentration limits recommended for designated superfund sites. The research herein consisted of two parts: (1) background research on recent coal-tar sealant data to determine individual PAH concentrations, and (2) an initial human health risk assessment (HHRA) for selected exposure pathways. In order to determine the exposure point concentration (EPC) of PAHs, two calculation methods were used based on the EPA’s 1993 relative potency factors (RPFs) and the more recent 2010 RPFs. This comparison of RPFs was essential to demonstrate the impact of the EPA possibly implementing an expanded PAH risk assessment. Of the three scenarios examined, worker exposure to volatilized PAHs in the air presented the largest LADD and cancer risk values of 3.25E-06 mg/kg-day and 2.37E-05, respectively, when using the 2010 RPF values for the calculations. These results have upheld the hypothesis of the potential PAH risk of certain populations that may become exposed to coal tar sealcoats.
A review of energy production systems through the utilization of poultry litter as a fuel source and determination of feasibility for North Carolina farming operations
(2013-07) Crawford, Kyle
ABSTRACT Crawford, Kyle. A review of Energy Production Systems through the utilization of poultry litter as a fuel source and determination of feasibility for North Carolina’s poultry farming operations (Under the direction of Linda Taylor) There is both a growing demand for clean energy consumption and an increase in agricultural production in order to both feed the world and continue to keep our global environment as clean as possible. The following dissertation aims to determine if clean and sustainable biofuel energy, utilization of poultry litter a fuel source, could be utilized to power the operation of a poultry farm, the same farm in which the litter was derived. Three techniques will be assessed: combustion, gasification, and digestion. In addition, a determination of feasibility associated with an average North Carolina poultry operation will be assessed for long term feasibility and applicability.
A review of the existing and prospective methods for the reuse and CO2 collected with carbon capture technology
(2016-05-05) Lempert, Michelle
Climate change, which is linked with fossil fuel combustion related Carbon Dioxide (CO2) emissions, is one of the major environmental problems that our society will be facing in the coming decades. Carbon capture and sequestration (CCS) methods coupled with CO2 reuse is a way to mitigate CO2 emissions. This research has two concurrent goals. First, the researcher will review current companies reusing CO2 collected via carbon capture technology to see how the CO2 reuse company landscape has changed since The Global CCS Institute’s 2011 report. The second portion of this report is the community engagement phase. The goal of this research is to assess a sample of subjects both on their current knowledge of carbon capture, sequestration (CCS) and reuse, and on their capacity to increase their understanding of this topic after viewing a short presentation.
A risk perception analysis: Toxicology education, its effect on quantitative judgments of risk, and the influence of demographic variables
(2015-05) Carlson, Daneil
Carlson, Daniel. A Risk Perception Analysis: Toxicology Education, its Effect on Quantitative Judgements of Risk, and the Influence of Demographic Variables. In order to study the influence of education on risk perception, particularly in toxicology with a focus on risk assessment, a survey was administered to 14 classes of undergraduate students at North Carolina State University before and after completing an undergraduate general education requirement course, Toxicology 201: Poisons, People, and the Environment. The multi-year surveys asked registered students to rank 10 activities, on a scale of 1-10, on their perception of the risk associated with them. Analysis of those survey results determined students’ relative changes in risk perception across each activity as a result of having taken the course, the influence of demographic characteristics (e.g., education and gender) on their overall risk perception, and the magnitude of the changes and inherent differences in risk perception. Statistical significance of changes in risk perception was determined by utilizing sign tests on pre- and post-survey data while statistical significance of differences in risk perception between demographic variables (e.g., males vs. females) was determined by utilizing Mann-Whitney U tests on pre-survey data. Results found a combined statistical and practical significance in the change in risk perception for all students with two of the activities - smoking tobacco products and living within 5 miles of a nuclear power plant; after completing the course, the former was ranked as more risky and the latter was ranked as less risky. Demographic variables were weak influencers of changes in risk perception, as risk ranking changes amongst the demographic variables studied were very similar to the overall risk ranking changes amongst the entire group of students. There was generally little variability in differences in risk perception between demographic variables and Mann-Whitney U tests were unable to establish statistically significant differences between risk rankings; despite this, certain differences were large enough to suggest a real affect, particularly when they were aligned with hypotheses supported by previous studies in risk perception, such as with the apparent difference in risk perception between men and women for the living within 5 miles of a nuclear power plant activity. Overall, the educational treatment was indicated as effective for changing risk perception for select activities related to toxicological hazards, and while demographic variables were weak influencers of changes in risk perception following the treatment, they suggested at inherent differences in risk perception that may be more apparent with additional study.
An Analysis of Water Quality in Public Water Systems, Private Wells, Groundwater, and Surface Water in North Carolina
(2024) Kayla Totten
Clean drinking water is essential for human life. The quality of publicly supplied drinking water is regulated by the Safe Drinking Water Act with maximum contaminant levels established for over ninety contaminants; however, the quality of private well water is not regulated. In this study, the quality of publicly supplied water and private well water was compared for nine counties in North Carolina with a focus on lead, copper, arsenic, iron, and manganese. Additionally, the quality of surface water and groundwater was analyzed for the nine counties since they serve as sources for the drinking water. Water quality data were obtained from publicly available sources including the North Carolina Department of Health and Human Services, Annual Drinking Water Quality Reports, and the United States Geological Survey Water Quality Portal. Upon analysis, private well water was found to have higher concentrations of lead, arsenic, iron, and manganese than publicly supplied water, thus highlighting the disparity between those relying on private well water and those with access to publicly supplied water. Private well water was found to have higher concentrations of lead than groundwater, indicating that lead likely enters the water from the corrosion of older plumbing systems that used metal pipes and plumbing. Copper also likely enters drinking water through the corrosion of older plumbing systems since private well water and publicly supplied water were found to have higher concentrations of copper than groundwater and surface water. Rural counties had higher concentrations of copper in publicly supplied water compared to urban counties, suggesting that the rural counties may have older plumbing systems. Publicly supplied water is filtered during drinking water treatment, likely removing arsenic, iron, and manganese. This was evidenced because the surface water, which publicly supplied water is sourced from, had higher concentrations of these contaminants compared to the publicly supplied water. Location played a role in the concentration of contaminants with high levels of arsenic found in counties known to have arsenic-containing rocks underground and counties in the Piedmont region having high concentrations of manganese. Overall, those relying on private wells are more likely to be exposed to drinking water contaminants than those with publicly supplied water, although it is important for all to have their water tested regularly to ensure it is safe and to help limit exposure to contaminants.
An Examination of Clickers in an Informal Educational Setting: Quantitative Improvements in Knowledge Gain for North Carolina Cooperative Extension Pesticide Applicator Training
(2014) Denlea, Gregory
Denlea, Gregory. Masters of Environmental Assessment. An Examination of Clickers in an Informal Educational Setting: Quantitative Improvements in Knowledge Gain for North Carolina Cooperative Extension Pesticide Applicator Training In 2012, the Extension Toxicology program at North Carolina State University (NCSU) received an award for pilot funds from the University of Kentucky’s Southeast Center for Agricultural Health and Injury Prevention to examine the effectiveness of audience response systems (ARS, “clickers”) in enhancing pesticide applicator safety and health training programs. Data was collected on pesticide applicator audiences’ learning and receptiveness to the technology. The pilot project assessed the impact of ARS on pesticide applicators’ learning and the potential for statewide expansion of ARS implementation in pesticide applicator programs. This paper contains the quantitative analyses of pre-intervention (without clickers) and post-intervention (with clickers) knowledge gains for pesticide applicators located in the 5 North Carolina (NC) Cooperative Extension Districts who participated in this pilot project. A questionnaire (see Appendix 1) was administered both before and after pesticide applicator required training to assess content knowledge, with each pesticide applicator serving as his/her own control. The quantitative results show that more pesticide applicators gave correct answers to the multiple choice questions after the sessions conducted using clickers (post-intervention) than provided correct answers after sessions without clickers (pre-intervention). Data collected for this pilot also suggests that the use of clickers has a positive impact on learning outcomes regardless of the education level, age, or experience of the pesticide applicator. Some implications are identified and recommendations are suggested regarding the on-going use of clicker technology for pesticide applicator training sessions.
ANALYZING POTENTIAL BENEFITS OF GREEN ROOFS IN FUTURE GROWTH SCENARIOS IN NEW HANOVER COUNTY
(2017-12) Flannery, Ian
ABSTRACT: Green roofs are gaining popularity in different parts of the world. This paper examines green roofs as a stormwater runoff management best management practice (BMP). Future growth scenarios, provided by New Hanover County’s long-term plan are likely to include a large increase in impervious surfaces. With the county being relatively small and already heavily developed, open space is at a premium. Traditional BMPs such as retention ponds require a large geographic footprint which is expensive, reduces buildable area, and requires significant land-disturbing activities which increases the risk for negative environmental impacts. The analysis was done by taking 2010 census data that included population, housing units, and jobs, and extrapolating these variables for three separate growth scenarios. The results were entered in the Environmental Protection Agency (EPA) Impervious Surface Growth Model to estimate the amount of impervious surface associated with each growth scenario. Rainfall volumes on the future impervious surface areas were calculated for a typical 30 minute, 1.5 inch rainfall event (a 1-year frequency storm for the area). Three different retention capacities were used in the analysis based on previous published studies. The analysis found that stormwater runoff volumes captured by green roofs could potentially have a significant impact on future stormwater planning for new development by replacing or reducing the footprint of traditional BMPs, saving money and space.
Assessing low-cost purple air particulate matter sensors
(2020-04) Wells, Heather
Wells, Heather. Masters of Environmental Assessment. Assessing Low-Cost Purple Air Particulate Matter Sensors With technological advances, low-cost light scattering particulate matter (PM) sensors have come into more prevalent use. They operate by sensing laser light scattering by particles. The scattered light correlates to particle count, and then sensor algorithms can determine the size- selective PM concentration based on the intensity of the light and assumptions about average particle density. Low-cost sensors are not as accurate as Federal Reference Methods (FRMs), with concentrations having lower accuracy and precision. In order to be able to evaluate air quality using low-cost sensors, it is necessary to test reproducibility of the data. In this study, four PurpleAir low-cost sensors were collocated with a Federal Reference Method to measure PM in a chamber with a wood stove as the source. A data correction scheme for the PurpleAir sensors was developed. While the PurpleAir sensors had high correlations with the tapered element oscillating microbalance (TEOM) reference instrument, their concentrations were roughly 50% lower than those produced by the TEOM. A limitation of the study was that the sensors were only tested in a chamber environment with no varying environmental conditions. The chamber experiment should be repeated seasonally to account for any sensor drift or changes from environmental factors and for a number of sources and ambient conditions.
Assessing the risk beliefs of occupational workers during sodium hypochlorite tank cleanings using a quantitative survey instrument
(2016-05) Persaud, Eric
Abstract Chemical tank cleaners’ occupational illnesses and deaths are largely unknown due to a lack of monitoring and research; further, there are no federal regulations that govern chemical tank cleanings. This pilot study details the development of a quantitative instrument to assess the risk beliefs of chemical tank cleaners, focusing specifically on tank cleaners who work with sodium hypochlorite. Through research on these occupational chemical workers’ risk beliefs, educators, safety engineers, and policymakers can make informed steps toward improving tank cleaner health and safety. The 18-item Likert type instrument developed in this pilot study was found to be psychometrically sound with a Cronbach's alpha of 0.772, and therefore can be a valuable tool in further studies of tank cleaner beliefs. The instrument, if properly modified, can target risk beliefs of tank cleaners working with a variety of hazardous chemicals, which can illustrate points of concern that should be addressed in developing education, interventions, and a standard federal code for tank cleaning.
Assessing trends in urban ground-level concentrations of nitrogen dioxide
(2015-05) Tillerson, Clint
Tillerson, Clint. Master of Environmental Assessment. Assessing Trends in Urban Ground-level Concentrations of Nitrogen Dioxide A review of the National Ambient Air Quality Standards (NAAQS) is required of the U.S. Environmental Protection Agency every five years. Included in the review typically is an assessment of health effects associated with air quality adjusted to meet the existing and potential alternative standards. In 2010, a 1-hour standard for nitrogen dioxide (NO2) was established to protect the population from short-term exposure found to cause adverse health effects in sensitive populations. Ambient monitoring data collected over the last 30+ years indicate NO2 concentrations have progressively lowered throughout all urban areas in the United States such that no areas are currently above the existing daily maximum 1-hour (DM1H) standard of 100 parts per billion. For the current and likely subsequent reviews of the NO2 NAAQS, it is necessary to adjust monitored concentrations upward to meet the existing standard (or some alternative if greater than existing conditions) in a manner that estimates realistic concentrations across the entire distribution. A prior analysis of ambient air quality data strongly supported that concentrations could reasonably be adjusted proportionally across the entire distribution, though there was evidence that the relationship might be nonlinear in the lower and upper percentiles of the distribution. This study revisits the trends in the reduction of ambient NO2 over time and compares two methods for adjusting NO2 concentrations upward. The first method assumes a proportional relationship exists across the distribution of DM1H concentrations while a second method assumes the same proportional relationship up to and including the 98th percentile DM1H and a nonlinear relationship above the 98th percentile. While this study is not intended to definitively define the appropriateness of either adjustment (proportional vs. proportional with nonlinear above 98th percentile DM1H) in representing the hypothetical high concentration air quality scenario, there is evidence to suggest assuming proportionality across the entire distribution could result in a significant underestimation of concentrations at the upper percentiles of the distribution.
Assessment of Polycyclic Aromatic Hydrocarbon Concentrations in Stream Bed Sediments Adjacent to Coal-Tar Sealcoated Parking Lots
(2012-11-25) Edwards, Olivia
Assessment of Surface Water and Sediment Impacts to Mountain Island Lake from Riverbend Steam Station Coal Ash Basin Discharges
(2017-12-03) Street, Andrew
Abstract A preliminary assessment of constituents of potential concern associated with coal combustion residuals (CCRs) in Mountain Island Lake (MIL) near the Riverbend Steam Station (RBSS) was conducted from March 2015 through August 2017. Sediment samples from the upper three-inches of the lake bottom were collected from the cove where the coal ash basin outfall for the RBSS discharges into MIL (hereinafter referred to as “the discharge cove”) in addition to samples from upstream and downstream reference coves. Total/whole surface water samples were also collected from the discharge cove in addition to samples from upstream and downstream locations. Copper (Cu), chromium (Cr), nickel (Ni) and polychlorinated biphenyls (PCBs) were detected in discharge cove sediment samples above Threshold Effect Concentrations (TECs) during one or more sampling events. Arsenic (As) was detected in discharge cove sediments above TECs, Probable Effects Concentrations (PECs) and North Carolina Residential Preliminary Soil Remediation Goals (Residential PSRGs). Concentrations of the above constituents in sediment indicated a gradient effect with maximum concentrations observed at the coal ash basin outfall decreasing with distance from the source. Aluminum (Al), As, cadmium (Cd), Cu, iron (Fe), manganese (Mn), zinc (Zn) and turbidity were detected in surface water samples at concentrations exceeding 15A North Carolina Administrative Code (NCAC) 02B .0211 and .0216 Surface Water Standards for Class WS-IV Waters (2B Standards) and/or United States Environmental Protection Agency (USEPA, aka EPA) Nationally Recommended Water Quality Criteria for Aquatic Life and Human Health (EPA Standards) during one or more sampling events. Al, Cu, Fe, and Mn were detected above 2B Standards and/or EPA Standards at upstream reference locations indicating that these metals may be naturally occurring. Of the remaining metals detections above 2B Standards and/or EPA Standards, As appeared to be correlated to the coal ash basin discharge. The results of this preliminary assessment suggest that although permitted coal ash basin discharges at the RBSS rarely exceed surface water quality standards, CCR related contaminants have accumulated in sediment at levels of concern. Given that localized exceedances of surface water standards are often permitted in a mixing zone, the potential for enrichment of hydrophobic and bioaccumulative contaminants with an affinity for organic matter in mixing zone sediment is high. Although the U. S. Environmental Protection Agency (USEPA) made several significant improvements to the National Pollutant Discharge Elimination System (NPDES) Program in 2015 for the steam power generating industry by significantly decreasing the volume of coal ash wastewater and the pollutant 5 loading associated with wet disposal practices, discharge monitoring programs at coal ash settling basins may not adequately detect and address all constituents of concern associated with coal ash basin effluent. Regulatory processes associated with issuing, renewing and closing NPDES permits at coal-fired power plants should be adequately protective not only of surface water but also sediment quality. NPDES permitting agencies should give consideration to specifying collection of sediment samples in close proximity to ash basin outfalls and to adding PAHs and PCBs to the target analyte list for sediment and fish tissue sampling programs that are often performed during the 5-year permit renewal process.
Assessment of Undergraduate Perceptions of Renewable Energy Technologies and Careers
(2011-12) Ebersohl, Richard Jr
EBERSOHL, JR, RICHARD DALE. Assessment of Undergraduate Perceptions of Renewable Energy Technologies and Careers. (Under the direction of Dr. Elizabeth Guthrie Nichols.) The development and implementation of renewable energy technology is becoming increasingly important as the world’s energy usage continues to rise. The shift in focus from fossil fuels to sustainable energy sources requires the addition of educational opportunities designed to support the growing need for renewable energy professionals. The purpose of this project is to identify and evaluate current North Carolina State University undergraduates’ knowledge and perceptions of renewable energy technologies, the value of an education in renewable energy technologies, and career opportunities in this emerging sector. An assessment was designed for a General Education Program course on Environmental Science that predominantly enrolls freshmen. The overall results suggest that students in this class have a basic understanding of renewable energy technologies but various misconceptions about the role these technologies currently play on a global scale. These results support an initiative to provide both science and non-science majors additional undergraduate curriculum for renewable energy assessment for non-engineers at North Carolina State University.
Bioavailability of PAHs in Aquatic Systems Using Passive Sampling: An Informative Piece
(2014-12) Gilfillan, Dennis
Abstract Bioavailability of PAHs in Aquatic Systems Using Passive Sampling: An Informative Piece. Dennis Gilfillan 2014 Polycyclic aromatic hydrocarbons are persistent contaminants in the aquatic environment that can cause both acute and chronic health effects, and in some forms are determined to be carcinogenic. They also can bioaccumulate in organisms that exist in contaminated ecosystems through ingestion and diffusive transport systems. Traditional methods of assessment of bioavailability –that is, the amount that is readily available for biological uptake and to circulate in the system -‐ requires grab sampling and solvent extraction methods that although quick and easy to perform can lead to over estimates of bioavailable concentrations. This can lead to conservative risk assessment with consequences in cost, delayed development of remediated sites, misidentified at risk sites, and misinterpreted information due to inaccuracies in the assessment. These traditional methods are countered with using passive samplers. These are based on diffusion uptake and once equilibrium is reached, a bioavailable concentration can be ascertained. These have been shown in the literature to be slower in attaining equilibrium, but have a benefit that the predicted concentrations are closer to actual bioaccumulated values in benthic organisms. With the use of performance reference compounds as well as site specific portioning coefficients and bioconcentration factors, estimates of risk due to contamination can be less conservative. The scope of this paper is to introduce passive samplers into the framework of modern risk assessment, review the previous literature on the subject of passive samplers use in both in-‐situ and ex-‐situ environments, and identify sources of future research to better assess bioavailability using passive samplers.
Blood Lead Levels in Construction Workers Performing Lead Abatement
(2022-12) Moran, Patrick
MORAN, PATRICK. Blood Lead Levels in Construction Workers Performing Lead Abatement. (Under the direction of Dr. Jennifer Richmond-Bryant). Lead abatement is a common practice in the construction industry. However, the job task generates airborne particulate lead, creating a potential workplace hazard exposure for workers if not managed properly. This exposure can cause severe acute and chronic illnesses. Entry and exit blood lead levels (BLLs) are required for all abatement workers under medical surveillance in OSHA § 1910.1025 Appendix C. BLLs can be used as a measurement of a worker’s exposure. The change from entry to exit BLLs can be analyzed in different project settings, abatement methods, engineering controls, and job trades to help determine best practices in mitigating a worker’s exposure. The Sen et al. (2002), Sokas et al. (1997), Levin et al. (1998), and Reynolds et al. (1999) studies all used different abatement methods for different abatement projects. Sen et al. (2002) analyzed scaffolders who performed mobilization/ demobilization erecting scaffolds in and around the containment while abrasive blasting was being performed. Sokas et al. (1997) studied crews who performed demolition and burning lead abatement versus workers who never performed demolition and burning lead abatement. Levin et al. (1998) compared BLL for iron workers on a bridge rehabilitation project in New York between the years 1993 and 1994 performing needle gunning and pneumatic chipping. Reynolds et al. (1999) compared the changes of BLL in construction workers in Iowa and Illinois across several different job occupations of laborers, painters, welders, and ironworkers. The findings of all four articles discovered that scaffold workers who were not performing active abatement tasks, such as mobilization and demobilization, could still have elevated BLL when working with containments or working in close proximity without necessary PPE. These four studies have unique abatement tasks and different engineering controls, despite there being increased BLL across tasks. Additionally, three abatement projects in 2018-2020 in New York (Manhattan Subway Project, Yonkers Pump Station Wastewater Treatment Project, and Hastings-On-Hudson Bridge Project) also used different abatement methods for different projects. All three projects also exhibited workers having varied increased BLLs. Abrasive blasting, needle gunning, plasma cutting, lead tape removal, mobilization/demobilization, and vacuuming were the tasks performed at the projects. The needle gunning, plasma cutting, lead tape removal, and mobilization/demobilization had the lowest BLL while abrasive blasting and vacuuming had the highest BLL. A literature review of the four articles was performed and each article had unique conditions and different abatement methods, similar to the three projects having different conditions and abatement methods. The data from the articles were compared to the data in the three projects. Based on findings presented in Sen et al. (2002), Sokas et al. (1997), Levin et al. (1998), and Reynolds et al. (1999) and the results from three abatement projects, workers’ risk of exposure exists regardless of abatement method but can be better managed by understanding which abatement methods and engineering controls should be used as best practice.

Browse

Browsing Master of Environmental Assessment Professional Papers by Title