Lab Scale Analysis of Anaerobically Digested Municipal Wastewater Treatment

Finding alternative sources of energy for the growing world’s demand is a challenging task being considered by many scientists and engineers. Various types of renewable energy alternatives are being investigated by researchers around the world. In addition to their capacity for nutrient, metal and pharmaceutical and personal care product contaminant removal from wastewater, the abundance of duckweed (i.e., Lemna and Wolfia sp.) in wetlands and wastewater lagoons, and their rapid growth and need for biomass harvesting suggests their potential as an inexpensive source of biomass for Biofuel production. Two lab-scales, 10 L anaerobic digesters initially seeded with municipal wastewater digester sludge were constructed, maintained and monitored over the course of more than 24 months using duckweed as the sole carbon source to evaluate its effectiveness as biogas feedstock. The pH, gas production rate and gas composition were measured on a daily basis. The results from these measurements show that the stabilization of harvested duckweed via anaerobic digestion also represents an efficient means of Biofuel production in the form of methane gas. Methane production, solids and COD stabilization, and gas composition results from the duckweed fed anaerobic digesters are discussed in detail in this paper. These results were used to determine potential energy production from biomass harvesting for the control of total P from a municipal wastewater treatment lagoon in Northern Utah

Plants for Stormwater Pollution Removal: Greenhouse Research and Field-Study at Green Meadows Subdivision Logan, UT

Much of the stormwater protection in Cache Valley is done with respect to prevention of TSS contamination during construction activities. Preventing contamination of stormwater from construction activities is critical, but stormwater can still be highly pollute

Reverse Osmosis in the Treatment of Drinking Water

An extensive review of the literature was conducted and results were evaluated for the use of the reverse osmosis process in the treatment of drinking water supplies. All aspects of reverse osmosis technology, including pretreatment requirements; membrane type and configuration; membrane cleaning and maintenance; and reverse osmosis removal of organics, inorganics, and microbial contaminants were incorporated inot the literature evaluation. A survey (Appendix E) of existing full scale reverse osmosis installations was also carried out and results of the survey are discussed. In light of data presented in the literature and results of the survey conducted, the following recommendations were made to prevent catastrophic membrane fouling occurrences and costly plant shutdowns in the future. 1) Conduct a comprehensive raw water quality evaluation. 2) Maintain continuous feed and product water quality monitoring. 3) Incororate process automation and system upset warning provisions in future installations. 4) Provide greatly improved training for reverse osmosis installation operators. The reverse osmosis system is particularly well suited for the treatment of water supplies which contain a number of contaminants that would otherwise require a combination of treatment processes for their removal, due to the ability of the reverse osmosis process to remove salts, organics, and a number of microbial contaminants. Effective pretreatment and routine backwashing, membrane cleaning, and disinfection must be carried out; however, if adequate system operation is to be assured

Engineering Treatment of Hazardous Wastewaters Utilizing Dye-sensitized Photooxidation

Studies were conducted to determine the applicability of photooxidation for the degradation of selected hazardous and refractory organic compounds. These photochemical oxidation reactions occur through the transfer of energy from electronically excited sensitizer molecules which attain excited states by absorbing visible light energy. Optimum conditions for photooxidation were established based on sensitizer concentration and reaction pH for four polynuclear aromatic pollutants. The rate of photooxidation was found to be independent of the initial substrate concentration for methylene blue-sensitized reactions, and dependent on substrate concentration for solutions without a sensitizing dye. Photolysis of substrate mixtures established acridine and anthracene as photochemically active substrates. Photochemical reaction data suggest predictable trends in substrate reactivity based on pKa values of both sensitizer and substrate, initial substrate concentration and light absorbance characteristics. The photoproducts formed during the photolysis of acridine were found to be more toxic than the parent compound. These reaction products appear to be atable and warrant further study

Soil Phase Photodegradation of Toxic Organics at Contaminated Disposal Sites for Soil Renovation and Groundwater Quality Protection

Accurate assessment of the potential for contaminated soil remediation requires detailed knowledge of the fate of waste constituents within the soil environment. For many non-biodegradable organics compounds, photochemical degradation may provide a potential pathway for the removal of such compounds from soil surfaces. A study was conducted to evaluate the rate of photodegradation of ten hazardous organic compounds from three soils, silica gel, and four soil minerals (kaolinite, montmorillonite, illite, and calcite) under conditions of controlled irradiation. In addition, the effect of siz amendment treatments (methylene blue, riboflavin, hydrogen peroxide, diethylamine, peat moss, and silica gel) on the rates of compound loss was also investigated. Soil and mineral samples were spiked with various combinations of m-cresol, quinoline, biphenyl, dibenzo[a]furan, fluorene, pentachlorophenol, phenanthrene, anthracene, 9H-carbazole and pyrene at either 500 or 1000 mg/kg initial soil concentration of each chemical. Amendments were applied to the soils and minerals and duplicate samples were irradiated in petri dishes under ultraviolet or visible light while spike controls were inclubated in the dark. Linear regression of soil/mineral contaminant concentration data showed that first order kinetic modeling best described the degradation process. Significant loss of anthracene occurred on all surfaces tested althrough the rate of loss varied with surface type and, for some surfaces, with the spiking solution concentration and chemical mixtures. Anthracene loss from silica gel was the msot rapid of all reactions observed. Skumpah soil, a light colored alkaline soil, yielded the greatest reduction in contaminant concentrations found in the soil studies. Calcium kaolinite displaed the most rapid kinetics of the mineral surfaces tested. Loss of the other test compounds was observed from only some of the surfaces investigated. Anthraquinone and fluorenone were identified as the major degradation products of the photoreaction of anthracene and fluorene. Under the conditions of this study, soild and mineral type, as well as surface renewal via mixing, were found to have more effect on degradation rates than any of the amendments that were tested

Contemporary Water Governance: Navigating Crisis Response and Institutional Constraints through Pragmatism

Water has often been the source of crises and their frequency will intensify due to climate change impacts. The Niagara River Watershed provides an ideal case to study water crises as it is an international transboundary system (Canada-United States) and has both historical and current challenges associated with water quantity and quality, which resonates broadly in water basins throughout the world. The aim of this study was to understand how stakeholders perceive ecosystems and the relationship with preferences for governance approaches in the context of water governance. An online survey instrument was employed to assess perceptions of the system in terms of resilience (engineering, ecological, social-ecological, or epistemic), preferences for governance approaches (state, citizen, market, and hybrid forms), and the most pressing issues in the watershed. Responses showed that, despite demographic differences and adherence to different resilience perspectives, support was strongest for governance approaches that focused on state or state-citizen hybrid forms. The validity of the resilience typology as a grouping variable is discussed. The roles of institutional constraints, pragmatism in governance approach preferences, and the influence of multiple crises are explored in relation to the context of the study site, as well as to water governance scholarship more broadly.Funding for this work, as part of the Climate Change Adaptation and Water Governance (CADWAGO) project, from Riksbankens Jubileumsfond, the Volkswagen Stiftung and Compagnia di San Paolo through the Europe and Global Challenges programme.https://www.mdpi.com/2073-4441/8/6/22

Ecosystem Perceptions in Flood Prone Areas: A Typology and Its Relationship to Preferences for Governance

A shift appears to be occurring in thinking about flooding, from a resistance-based approach to one of resilience. Accordingly, how stakeholders in flood-prone regions perceive the system and its governance are salient questions. This study queried stakeholders’ internal representations of ecosystems (resistance- or resilience-based), preferences for governance actors and mechanisms for flooding, and the relationship between them in five different regions of the world. The influence of personal experience on these variables was also assessed. Most respondents aligned themselves with a resilience-based approach in relation to system connectedness and response to disturbance; however, respondents were almost evenly split between resistance- and resilience-based approaches when considering system management. Responses generally were considered to hold for other disturbances as well. There was no clear relationship between internal representations and preferences for governance actors or mechanisms. Respondents generally favoured actor combinations that included governments and mechanism combinations that included regulations and policies. Those who had personal experience with flooding tended to align themselves with a resilience-based internal representation of system management, but personal experience showed no clear relationship with governance preferences. The findings support an evolutionary perspective of flood management where emerging paradigms enhance preceding ones, and prompt a critical discussion about the universality of resilience as a framing construct.Financial support for the CADWAGO project from Riksbankens Jubileumsfond, the Volkswagen Stiftung and Compagnia di San Paolo through the Europe and Global Challenges programme, as well as the Swedish Civil Contingencies Agency (MSB).https://www.mdpi.com/2073-4441/8/5/19

Toxicity and Environmental Health Hazards of Petroleum Products in Wells Used for Drinking Water in the Intermountain West

Introduction: Groundwater is aprimary source of drinking water for about 50 percent of the population in the U.S. This source of drinking water has been generally regarded as safe from contamination. Several papers indicate that numerous underground storage tanks containing petroleum products may be leaking and contaminating public water supply wells across the U.S. (Matis, 1971; Ferguson, 1979; Woodhull, 1981; Burmaster and Harris, 1982; Lehman, 1984; Dowd, 1984; OTA, 1984). A study conducted by the Utah Cureau of Solid and Hazardous Wastes in 1985 concluded that there are at least 2,314 underground steel tanks, most of which are used to store gasoline and diesel fuel, in Utah which are more than 20 years old and may be leaking. Contamination of well water by petrolium products from leaking underground storage tanks (LUST) is a matter of increasing concern. LUST pose a serious threat to the groundwater and public health. Leaks of petroleum products from LUST at industrial plants, commercial establishments (e.g., automobile service stations), and other operations could be expected to increase the types and concentrations of petroleum products in groundwater used for drinking and exposure of humans to the toxic effects of these chemical compounds. Petroleum products are persistent and highly mobile contaminatns which are difficult to remove from groundwater. In addition, many of these chemicals are known or suspected carcinogens or mutagens which can pose undesireable human health risks (e.g., cancer, birth defects, and other chronic conditions) at 10 ppb and below (Council on Environmental Quality, 1980). There is a need for more research on the types and concentrations of petroleum products (e.g., benzene, toluene, ethylbenzene) found in public water supply wells used for drinking water and the immunotoxic and neurotoxic effects of these organic compounds. The objectives of this research project were: 1. To characterize petroleum products in raw water from wells used for drinking water in selected areas (industrial, commercial, and other) of Utah. 2. To evaluate the toxicity of selected petroleum products in experimental animals, with emphasis on the following: a. Immunotoxic and hypersensitivity effects. b. Neurotoxic and behavioral effects