Thesis (Ph.D.)--Murdoch University, 2008. / Thesis submitted to the Faculty of Sustainability, Environmental and Life Sciences. Includes bibliographical references (leaves 118-134)

Eradicating poverty, malnutrition, and the burden of disease have been included as three of the major issues facing the world. The United Nation member countries, having set forth the Millennium Development Goals, have committed themselves to solving these problems. Two major factors which affect solutions to these problems are increasing water stress and implementing improved sanitation. Integration of tilapia aquaculture and reuse of wastewater has been suggested as a solution which addresses both of these factors. The objective of this study is to examine the feasibility, and explore the benefits and drawbacks, to implementing small community wastewater fed (WWF) aquaculture systems in the developing world. The water quality characteristics of treated effluent from nine wastewater treatment (WWT) plants were compiled from other studies. The concentration of total nitrogen in the effluent and the flow rate were of most importance, as they were used to calculate the nitrogen loading at each WWT plant. The nitrogen loading was then used to estimate the total pond size which could be supported by each WWT plant, the expected yearly yield for tilapia, and the percentage of the population who would benefit from provision of protein associated with the integration a fish farming system with the WWT plant. Results show that WWF, semi-intensive tilapia culture can provide 10 grams per day of dietary protein for 11% - 52% of the population of the communities in this study when integrated with a community managed wastewater treatment system. To assess potential risks to human health, associated with WWF aquaculture, the level of fecal coliform (FC) contamination was compared to the standard set by the World Health Organization; less than 105 FC per 100 mL for reuse in fish ponds. The level of FC contamination in the WWT plant effluents ranged from 653 to 1.78 × 105 FC per 100 mL, exceeding this standard. Given the context, the level of fecal coliforms should not rule out integrated reuse and aquaculture as an option. The nutrients found in wastewater are valuable resources in tilapia culture; therefore, allowing their persistence through treatment for reuse, while optimizing wastewater treatment technologies for pathogen removal is an appropriate solution for small communities in developing countries for reducing poverty, malnutrition, and disease burden of waterborne illnesses.

Soil-aquifer treatment (SAT) has been proposed as a method for reusing treated municipal wastewater. SAT is characterized by alternating cycles of aerobic and anaerobic conditions in the subsurface, in response to alternating cycles of flooding and drainage of a surface impoundment. It is not yet known how these alternating redox conditions affect the removal of potentially harmful endocrine-disrupting compounds (EDCs) from treated effluent. The overall objective of my doctoral research is to determine the fate of EDCs in alternating aerobic/anoxic/anaerobic conditions under simulated SAT conditions. To assess the fate of EDCs in simulated SAT conditions, I first had to develop appropriate analytical methods. Prior researchers have developed sophisticated analytical methods for measuring low concentrations of EDCs in water. However, it is not inherently clear which of these methods is preferable for analysis of any particular set of environmental samples. Therefore, in order to compare the analytical methods, solid-phase extraction (SPE) and solid-phase micro-extraction (SPME) were compared for the analysis of two EDCs, bisphenol-A (BPA) and 17B-estradiol (E2), in water samples of water. Following extraction by SPE or SPME, the target EDCs were derivatized (silylated) and then analyzed by gas chromatography (GC) with mass spectrometry (MS). Also, the performance of two candidate derivatization agents, N,O-bis-(trimethylsiyl) trifluoroacetamide (BSTFA), N-methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), was compared. SPME is more convenient, is less labor-intensive, and allows for analysis of smaller sample volumes, but it is expensive because fibers need frequent replacement, and the range of linearity was limited. SPE has a lower material cost and allows for the analysis of a broader range of concentrations, but it is more labor-intensive and large sample volumes may be required. Therefore, the selection of which method is "best" depends upon the constraints (time, money, sample volume, acceptable detection limit) associated with any particular set of samples. The two derivatization agents performed equally when used in conjunction with SPE, but MSFTA yielded higher peak areas for headspace (on-fiber) derivatization during SPME. To investigate how alternating redox conditions of SAT may affect the removal of harmful EDCs, a simulated SAT systems were constructed in 4-L reactors with 500 g of sediment (collected from a wetland) and 3 L of treated effluent from a municipal wastewater treatment plant; then BPA and E2 were spiked into reactors, two common EDCs often found in treated wastewater. Redox conditions in the mesocosms were controlled by switching the air between air (to induce aerobic conditions) and nitrogen (to induce anaerobic conditions); the length of the anoxic/anaerobic cycles was varied to determine how this affects biodegradation of the target EDCs. The mesocosm environment was supplemented with either nitrate or sulfate to serve as potential electron acceptors during the anoxic/anaerobic cycles. In addition to monitoring the concentrations of the target EDCs in the mesocosms over time, I also monitored the concentration of dissolved oxygen in the water; the redox potential; the concentrations of nitrate, nitrite, and sulfate; and the concentration of bacteria in the water (estimated via flow cytometry). BPA was biodegraded only during aerobic cycles, but E2 was biodegraded during both aerobic and anoxic/anaerobic cycles. Whenever the redox conditions in the system were switched, there was a temporary drop in the bacterial population, followed by a recovery of the population. When redox conditions were switched from anoxic/anaerobic to aerobic, biodegradation of the target EDCs commenced after a lag period during which no biodegradation was observed. The lag time for biodegradation in the aerobic cycle was longer when the anaerobic cycles were longer in duration. More biodegradation of E2 was observed under anoxic conditions than under anaerobic conditions. SPE and SPME methods that included derivatization agent are useful method for detection and quantification of EDCs in water. I concluded that SAT is a viable technology to produce potable water from treated WWTP effluent, but the optimal length of flooding and drying cycles of SAT required removing the targeted contaminants during infiltration through the vadose zone.

The U.S. Green Building Council (USGBC) is the developer of the Leadership in Energy and Environmental Design (LEED™) green building scoring system. On first inspection of LEED points, few address water efficiency. However, water management encompasses other points beyond the Water Efficiency (WE) category. In general, the industry is apt to take a somewhat compartmentalized approach to water management. The use of alternative water sources or the reuse of wastewater significantly complicates the water budget picture. A total water management systems approach, taking into consideration water from various sources, both inside and outside the building, should be implemented in order to devise a strategy for optimal reduction of potable water consumption and wastewater generation. Using the STELLA software to create an integrated building water management (IBWM) model provides stakeholders with a tool to evaluate potential water savings under dynamic conditions for a specific project site. Data collection for IBWM model calibration also shows that water consumption trends are unique to each project, and using LEED assumptions about water usage can overestimate or underestimate potential water savings.

This thesis provides much needed representative sample data for reuse life of fully seated and torqued locknuts. Most national requirements for prevailing torque locking fasteners only specify unseated reuse life. This could create a potentially dangerous situation if unseated is misinterpreted for seated. This thesis provides comparative data for seated verses unseated configuration. Six aerospace, 3 all-metal and 3 nylon insert, and one non-aerospace locknuts were tested at preloads levels of unseated, 66%, 75%, and 85% of yield of bolt. The locknuts tested are MS21043-4, NAS1291-4, NAS1805-4, MS17825-4, MS21044D4, NAS1021N4, and Grade 8. A fixture was created in order to allow for the simultaneous data collection of the applied preload and torque, along with the removal of preload without loosening the locknut. The results from testing indicate the number of reuse cycles is greater for nylon locknuts than the all-metal locknuts. Large losses, on the order of 20-50%, in prevailing torque occur between the first and second cycle of each locknut under all preloads. Tightening Torque required to achieve a certain preload was found to increase with reuse. Application of lubrication to nylon locknuts had a significant effect, reducing the reuse life and prevailing torque performance. The testing indicated the effect of preload reduced the number of reuse cycles to failure, failure occurs when the prevailing torque is measured outside the range of 3.5 to 30 in-lb. All locknuts survived unseated and 66% Y preload testing, except MS21043 which lasted about 14.5 reuse cycles at 66% Y and NAS1805 which survived 8 reuse cycles for unseated and 12.67 reuse cycles at 66% Y. NAS1805's loss of reuse life is due to hardness and material compatibility issues. The scatter of the torque measurements was low for the first three to five cycles, then as the coatings and lubrications are worn the scatter increases. The data collected from testing agrees with the torque friction equation.

The purpose of this research is to determine if anaerobic adhesive can be used as a prevailing torque locking feature. Maintaining preload in critical joints is the usual standard that anaerobic adhesives are held to in aerospace and other industry. To test if anaerobic adhesive can be used as a prevailing torque locking feature a test procedure was developed and implemented to measure the removal torque of threaded fasteners after an allotted cure time. In total, 191 threaded fasteners of different material and coatings were tested in the unseated and seated states with various strengths and varieties of anaerobic adhesive. A series of three tests were conducted: initial use, reuse with no added anaerobic adhesive, and a third test with added product to the bolt and nut to see how removal torque would behave in these conditions. It was found that using anaerobic adhesive as a prevailing torque locking feature is viable in many cases. No published work to date analyzes anaerobic adhesive at the standard of a prevailing torque locking feature.

As water stresses increase across the U.S., interest in household water reuse is growing. Such reuse typically focuses on light greywater, that is all wastewater generated in the house excluding toilet waste and kitchen wastewater. As this practice becomes more widespread, higher level reuse is expected to require greater greywater treatment prior to reuse. Membrane bioreactors (MBRs) are an attractive technology for this application because they offer a robust combination of treatment processes and are already used in some households in countries such as Japan. This research sought to understand the role of phosphorus availability in determining the quality of effluent from MBR treatment of light greywater because phosphorus concentrations are expected to be low with phosphorus phased out of many consumer products. Less than 30 [mu]g/L of dissolved orthophosphate was present in synthetic greywater made from three common household products, and no measurable amount of dissolved orthophosphate was found in real greywater, but low concentrations of particulate phosphate were detected. These concentrations were well below levels believed necessary to achieve full BOD₅ removal in biological treatment. Nevertheless, MBR performance was not adversely affected until no supplemental phosphorus was provided. Measurement of extracellular enzyme activity showed an increase in the ratio of phosphatase activity to total glycosidase activity with declining phosphorus concentration, providing an early indication of nutrient stress before changes in effluent water quality were detected. Removal of three xenobiotic organic compounds (XOCs) in treatment of synthetic greywater was also evaluated under conditions of phosphorous limitation and balance. Abiotic removal mechanisms were not deemed to be important, but removal of methylparaben and sodium lauryl sulfate via biodegradation responded to nutrient limitation similarly to overall COD removal while removal of diethyl phthalate was affected to a greater extent. Measurement of plasmid DNA concentrations was evaluated as a potential indicator of the effect of nutrient limitation on plasmid-mediated biodegradation of XOCs. An overall reduction in the plasmid content was observed in all cases under conditions of phosphorus limitation; however, the extent of reduction was reactor dependent. / text

Marginal soils, including loose sands, soft clays, and organics are not adequate materials for construction projects. These marginal soils do not possess valuable physical properties for construction applications. The current methods for remediation of these weak soils such as stone columns, vibro-compaction, etc. are typically expensive. Waste materials such as scrap tires, ash, and wastewater sludge, offer a cheaper method for stabilizing marginal soils. As an added benefit, utilizing waste materials in soil stabilization applications keeps these materials from being dumped into landfills, thereby saving already depleting landfill space. Included in this report is an extensive investigation into the current state of research on waste and recycled materials in construction applications. Also included is an investigation on actual implementation of this research in construction projects. Upon completion of this investigation, an effort was made to determine waste materials specific to the state of Florida (waste roofing shingles, municipal solid waste ash, waste tires, and paper mill sludge) that could be used in stabilizing marginal soils through soil mixing techniques. Changes in the engineering properties of soils as a result of adding these waste materials were studied and recommendations on implementing these effects into construction applications are offered.

This report, situated in Birmingham, Alabama, explores the best strategies for implementing arts-based adaptive reuse development in vacant or available downtown buildings. Through adaptive-reuse, a strategy of repurposing old buildings for new uses, the arts sector in Birmingham can be nurtured and strengthened. In this report, I present the major implications associated with the strengthening of the arts community. These implications include economic development, central city revitalization, community building, and gentrification. / text

This work is part of a broader, multi-year investigation of Maui Island’s freshwater resources. Maui Island faces multiple resource constraints, including water, land, energy, and capital, and these resource constraints could become relevant over the next forty years. Not only does Maui face potential changes to its water and other systems due to external factors beyond its control, like anthropogenic and other climate changes, but Maui also could make developmental choices that will impact how its resource systems interact. In particular, this work looks at Maui’s freshwater systems as they relate to energy, waste, and environmental systems. This report provides a foundation for future scenario analysis on the island that will aim to characterize potential synergies and hazards of choices like increased food production, local fuel production, and increased use of renewable energies. / text