Browsing by Subject "Environmental"
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Item Open Access An Assessment of Sustainable Water Management at University Campuses(2011) McHugh, Amani NSustainable water management is needed to ensure quality supplies of our vital water resources in the face of growing human demand for water, high levels of pollution, and increasing spatial and temporal variability associated with climate change. An integrated approach to water management is recommended to address current water challenges, which are often interrelated with other environmental, economic and social issues. Universities and colleges have missions, resources, and contexts that could enable them to lead the process of developing and applying sustainable and integrated water resource management (IWRM). The opportunity to exemplify integrated water management has grown as institutions of higher education have made progress towards incorporating environmental sustainability into teaching, research, and campus operations. This dissertation examines the issue of campus water management at institutions of higher education through a review of campus sustainability literature, a survey of sustainability and facilities managers, and case studies of three campus water-related projects.
Findings from the review of campus sustainability literature and websites suggests water is less of a campus management priority than issues such as energy and climate change; furthermore, where water is addressed, the focus is on water conservation, while water quality management is overlooked. IWRM is not explicitly discussed in the campus sustainability literature reviewed, though principles relevant to IWRM are included in some campus sustainability declarations and programs. Results from the survey substantiate the findings from literature review that water management is less of an institutional priority than energy management and water quality management is often underemphasized in campus management. According to the survey respondents, campus water management at the institutions represented was on average just adequately managed and institutions were minimally prepared to deal with several types of future water problems. Facilities managers tended to rate their institution's water management as slightly more effective compared to sustainability coordinators. Many campuses relied on top-down, engineering based water management approaches, rather than integrated and interdisciplinary water management. Individual initiatives, municipal codes and policies, campus community sustainability awareness, and campus environmental projects served as drivers for more sustainable water management, while budget constrains were a common barrier. Logistic regression analysis of the survey data revealed that institutions featuring stream and wetland restoration projects had greater odds of being described as having a developed watershed plan and taking into consideration multidisciplinary approaches to water management.
Case studies showed that wetland creation and restoration projects can serve as effective teaching and research laboratories for institutions of higher education, but that none of the studied cases fully exemplified IWRM in their operation. Of the three cases studied, the Stream and Wetland Assessment Management Park project at Duke University most closely demonstrated a campus project designed and developed to address water problems in the campus watershed, while also offering an effective outdoor teaching and research laboratory for hundreds of students, professionals, and researchers. The Olentangy River Wetland Research Park case at Ohio State University exemplified the potential for wetland creation and restoration projects to serve as a facility for educating thousands of students and visitors, training dozens of water experts, and influencing wetland and water resource management beyond the campus. The Radford University Stormwater Treatment Wetland Project case illustrated the potential for institutions with limited space and resources to establish effective outdoor teaching laboratories using environmental features already present or in development on campus.
Findings from the review, survey and case studies all point toward the need and opportunity for institutions of higher education to make greater efforts at implementing and promoting sustainable and integrated water resource management. Literature review and survey findings reveal that water is frequently overlooked as environmental resource at universities and colleges, while other environmental issues such as energy, climate change and recycling are prioritized in sustainability plans and efforts. Universities and colleges have made progress addressing water conservation, while water quality and stormwater need further attention and an integrated approach for more effective management.
Item Open Access BIO-BASED PLASTIC PACKAGING: A TOOL TO HELP ORGANIZATIONS ANALYZE THE TRADE-OFFS BETWEEN BIO-BASED AND CONVENTIONAL PLASTICS(2007-09-18T19:55:21Z) Bellucci, NinaAn increasing number of companies are exploring ways to improve their environmental footprint. Some environmental benefits are offered by bio-based plastic packaging; however, this approach requires trade-offs. For example, plastic bottles made with polylactic acid (PLA), a bio-based plastic resin, lack the impact strength offered by plastic bottles made with polyethylene terephthalate (PET). Other trade-offs include diminished shelf life capabilities, increased cost, and recycling infrastructure. In particular, displacement of recyclable plastic packaging with plastics made from renewable resources has created controversy among environmental advocates. Despite its performance, cost, and recycling shortcomings, PLA offers an attractive choice to some because it represents the transition towards use of renewable resources. In an attempt to address trade-offs, I developed an analytical framework with assistance from key stakeholders. After identifying the fundamental objective of the best choice of resin for the manufacture of plastic bottles, I surveyed stakeholders to create a list of essential packaging criteria, with the three major criteria being performance as a bottle material, cost, and environmental impact. I relied on private interviews with industry experts and conference presentations to gather bottle data for four resins: PLA, PET, high density polyethylene (HDPE) and polypropylene (PP). The framework for comparison was Multiattribute Utility Theory (MAUT), a methodology designed to address trade-offs among multiple objectives to achieve an overall objective. Based on the survey results and best available data as input for MAUT, PET was the best choice of resin for the beverage bottle. This non-bio-based plastic emerged as the top choice largely due to its superior performance on criteria such as strength and shelf life. Further analysis of the characteristics of the four plastics showed that even if all environmental and cost characteristics of the bio-based plastic, PLA, were as favorable as any of the other plastics I analyzed, PLA still would not come to the top. Only if PLA’s performance as a bottle material (strength, etc.) increased several fold would PLA become the top choice among the four I analyzed. Similarly, analysis of the weighting of the criteria showed that increasing the weights on environmental criteria, compared to performance and cost criteria, cannot elevate PLA to the top choice, mainly because HDPE has desirable environmental characteristics such as recyclability. Only increasing the weight on environmental criteria such as greenhouse gas emissions while decreasing the weight on all other environmental criteria would allow PLA to become the top choice among the four bottle materials I analyzed.Item Open Access Condition Based Maintenance of Lead Acid Batteries and Environmental Responsibility(2010-04-30T19:37:34Z) Kristoffersen, AsgeirCondition Based Maintenance of Lead Acid Batteries and Environmental Responsibility By Asgeir Kristoffersen May 2010 The increase in demand for electrical energy is putting pressure on outdated utility infrastructures and services at the same time that advances in business operations are requiring stable and sufficient sources of power for sensitive operations. A key component of the electrical grid is energy storage and lead acid batteries remain the most cost effective solution. The efficient and prudent use of lead is at best difficult at a time that lead acid batteries are being called upon to provide backup power for critical power applications. This study seeks to use lead acid batteries efficiently thereby reducing the amount of lead acid in our environment. The research consisted of a case study of US electrical power substations, an integral part of the power grid. The case analysis compared traditional maintenance practices of lead acid batteries versus the use of battery condition monitoring. There is a strong business case to be made for investing in condition monitoring to manage the battery assets within power substations. This will ensure that the batteries will function when required. The case study demonstrated that once condition monitoring was installed the number of preventative maintenance visits to a remote site was reduced by 85% with a commensurate reduction in the number of medium duty trucks on the nation’s roads. The avoided CO2 emissions presented a compelling argument for condition monitoring. Condition monitoring and the resultant condition based maintenance will drive infrastructure reliability higher and result in the more efficient use of lead acid batteries with the added benefit of CO2 reductions. There are hundreds of other applications for this technology and with strong management buy-in it is possible to overcome the resistance to change from traditional maintenance practices.Item Open Access Detection and Quantification of Single-walled Carbon Nanotubes in Environmental and Biological Samples for Evaluation of Fate, Transport and Bioaccumulation(2017) Liu, XuehongSingle-walled carbon nanotubes (SWCNT) are unique, anthropogenic allotropes of nanoparticulate black carbon. As numerous industrial and commercial uses of SWCNT result the heavy expansion of production of this material, the release of SWCNT is likely to occur, increasing their level in air, water and soil. SWCNTs have been shown to cause adverse impact in organisms from direct exposure through ingestion or inhalation. In addition to direct exposure, SWCNT can also induce toxicity to organisms by indirect exposure such as adsorption of hydrophobic contaminants (HOCs). One unique property of SWCNT is the quantized nature of their electronic structure, which is dependent on the chiral wrapping angle of the sp2 hybridized graphene sheet that comprises the wall of each SWNT species. Using probe HOCs – one planar polycyclic aromatic hydrocarbon (PAH)14 C-naphthalene and one halogenated aromatic 14 C-hexachlorobenzene and purified conductive and semiconductive SWCNT species, my first study aimed at assessing the role of SWCNT electronic structure on HOC sorption. Despite their differences in electronic structures, the results indicated that overall the electronic structure does not influence the adsorption of HOCs. However, due to the large specific surface area, SWCNT have a general high affinity for HOCs. Upon release of SWCNT into aquatic environment, SWCNT have the potential to affect the distribution of organic contaminants by acting as strong sorbent.
A significant barrier to studying toxicity of SWCNT to animal models is the lack of in vivo techniques to track and quantify SWCNT for assessing their distribution, transport and bioaccumulation. The fluorescence resulting from the unique band gap of each species of semiconductive SWCNT allows the detection and quantification of a bulky SWCNT sample using near infrared fluorescence spectroscopy (NIRF). NIRF is highly sensitive to detect SWCNT in biological tissues due to the low fluorescence in the near infrared region from biological samples. Two exposure routes were investigated using NIRF: ingestion from dietary track using fathead minnow (FHM) fish model in an aquatic environment and inhalation through lung using mouse model. The SWCNT extraction conditions were optimized and validated using spike recovery experiments. SWCNT were extracted from fish tissues, intestine, and liver using ultrasonic extraction in 2% sodium deoxycholate1extraction. Proteinase K digestion was needed for dissolving mouse lung prior to SDC extraction. The quantification results showed that while SWCNT readily passed through fish dietary track with minimal partition into the lumen tissue and caused no acute toxicity; SWCNT was less mobile in respiratory system and was responsible for the lung-term pulmonary disease induced.
The fate, transport and bioaccumulation of SWCNT are essential information for risk assessment and making environmental regulations for nanomaterials. Currently the lack of standardized sensitive characterization and quantitative analytical methods for SWCNT determination at the current levels in the environment is one major barrier for evaluation of their real impact to the environment. NIRF is sensitive for environmental samples. However, this technique is not sensitive to all types of SWCNT. Metal catalysts are widely used in synthetic production of SWCNTs, leading to total metal content ranging from 5 - 30%. The metal: metal ratios and metal: carbon ratios of SWCNT are very distinctive from many geological materials. A metal fingerprinting approach was developed by monitoring the metal type and metal: metal ratios, along with elemental carbon content. SWCNT can be principally quantified using inductive coupled plasma mass spectrometry (ICP-MS). Metal content, metal: metal ratios, elemental carbon and metal: carbon ratios were analyzed for two aerosol matrices, the urban dust NIST SRM 1649b and aerosol collected at Duke University using three types of SWCNT: SG65 SWCNT, SG65i SWCNT and P2 SWCNT. Results demonstrated that the metal finger approach worked well with all aerosol matrices with detection limits near ng m-3. It worked best with elements that were less abundant in the background such as Co and Y. This method offers a robust and economic approach for application to occupational spaces for monitoring possible SWCNT release.
Applying a similar approach in sediment presents a significant challenge as background metals present in sediment complicates such analyses. To overcome these challenges, we have applied density gradient ultracentrifuge (DGU) to isolate and separate SWCNT in sediment extracts prior to both NIRF and ICP-MS analysis. Several types of SWCNTs (arc discharge, CoMoCat, and HiPCO) were spiked and subsequently extracted from estuarine sediments. SWCNTs were separated into different bands after DGU, primarily into two distinct horizons (one showed near infrared fluorescence, while the other did not). Two techniques,near-infrared spectroscopy (NIRF) and ICP-MS, were applied for quantitation of SWCNTs in these bands. Results indicate excellent separation of SWCNT from interferences in sediments. We have also discovered an apparent disconnect between the metal catalyst particles and SWCNT during density gradient ultracentrifuge separation. It is clear that the SWCNT (within the NIRF band) is not physically associated with metal catalyst. This result was further confirmed using single-particle ICP-MS. Although DGU separation seems to be an outstanding method for isolating SWCNT from aquatic sediment for analysis, our current findings indicate that metal fingerprints derived from residual catalyst may not be a good tracer for SWCNT occurrence and fate in marine sediments, as the associated metal catalyst particles in SWCNT preparations might be transported in different ways relative to the SWCNT.
Overall, my research explored several analytical techniques to detect and quantify SWCNTs at their relevant concentration in various environmental matrices. These techniques will provide essential information for evaluating the environmental impact based on SWCNTs fate, transport and bioaccumulation in the environment.
Item Open Access Exploring Associations Between Prenatal PFAS Exposure and Childhood Asthma(2021-04-28) Bogar, LanePer- and polyfluoroalkyl substances (PFAS) are a large class of man-made chemicals used extensively in consumer and industrial products, making them ubiquitous in the built and natural environment. These chemicals pose a cause for concern, as there is increasing experimental and epidemiological evidence suggesting that exposure is associated with adverse health outcomes, especially prenatal PFAS exposure during critical periods of development. This study explored the associations between prenatal PFAS exposure, measured via maternal serum levels collected during pregnancy, and childhood asthma incidence in a cohort of 155 women, and 165 of their children from North Carolina. PFAS were detected in all serum samples and levels were similar to those in the general population. Statistical analyses incorporated potential predictors and covariates, including sex, age and race. After adjusting for these factors, statistically significant associations with asthma were found. Future efforts are needed to examine prenatal PFAS exposures and respiratory outcomes in later life.Item Open Access Unnatural History: Ecological Temporality in Post-1945 American Literature(2016) Evans, Rebecca McWilliamsWhile environmental literary criticism has traditionally focused its attention on the textual representation of specific places, recent ecocritical scholarship has expanded this focus to consider the treatment of time in environmental literature and culture. As environmental scholars, activists, scientists, and artists have noted, one of the major difficulties in grasping the reality and implications of climate change is a limited temporal imagination. In other words, the ability to comprehend and integrate different shapes, scales, and speeds of history is a precondition for ecologically sustainable and socially equitable responses to climate change.
My project examines the role that literary works might play in helping to create such an expanded sense of history. As I show how American writers after 1945 have treated the representation of time and history in relation to environmental questions, I distinguish between two textual subfields of environmental temporality. The first, which I argue is characteristic of mainstream environmentalism, is disjunctive, with abrupt environmental changes separating the past and the present. This subfield contains many canonical works of postwar American environmental writing, including Aldo Leopold’s A Sand County Almanac, Edward Abbey’s Desert Solitaire, Annie Dillard’s Pilgrim at Tinker Creek, and Kim Stanley Robinson’s Science in the Capital trilogy. From treatises on the ancient ecological histories of particular sites to meditations on the speed of climate change, these works evince a preoccupation with environmental time that has not been acknowledged within the spatially oriented field of environmental criticism. However, by positing radical breaks between environmental pasts and environmental futures, they ultimately enervate the political charge of history and elide the human dimensions of environmental change, in terms both of environmental injustice and of possible social responses.
By contrast, the second subfield, which I argue is characteristic of environmental justice, is continuous, showing how historical patterns persist even across social and ecological transformations. I trace this version of environmental thought through a multicultural corpus of novels consisting of Ralph Ellison’s Invisible Man, Ishmael Reed’s Mumbo Jumbo, Helena María Viramontes’ Under the Feet of Jesus, Linda Hogan’s Solar Storms, and Octavia Butler’s Parable of the Sower and Parable of the Talents. Some of these novels do not document specific instances of environmental degradation or environmental injustice and, as a result, have not been critically interpreted as relevant for environmental analysis; others are more explicit in their discussion of environmental issues and are recognized as part of the canon of American environmental literature. However, I demonstrate that, across all of these texts, counterhegemonic understandings of history inform resistance to environmental degradation and exploitation. These texts show that environmental problems cannot be fully understood, nor environmental futures addressed, without recognizing the way that social histories of inequality and environmental histories of extraction continue to structure politics and ecology in the present.
Ultimately, then, the project offers three conclusions. First, it suggests that the second version of environmental temporality holds more value than the first for environmental cultural studies, in that it more compellingly and accurately represents the social implications of environmental issues. Second, it shows that “environmental literature” is most usefully understood not as the literature that explicitly treats environmental issues, but rather as the literature that helps to produce the sense of time that contemporary environmental crises require. Third, it shows how literary works can not only illuminate the relationship between American ideas about nature and social justice, but also operate as a specifically literary form of eco-political activism.