Biodegradation of petroleum hydrocarbon can be an effective treatment method applied to control oil pollution in both fresh water and marine environments. Hydrocarbon degraders, both indigenous and exogenous, are responsible for utilizing petroleum hydrocarbon as their substrate for growth and energy, thereby degrading them. Biodegradation of hydrocarbons is often enhanced by bioaugmentation and biostimulation depending on the contaminated environment and the competence of the hydrocarbon degraders present. An evaluation of the performance of the biological treatment of petroleum hydrocarbon by the hydrocarbon degrading microbes at the Brayton Fire School??s 4 million gallon per day (MGD) wastewater treatment plant was the main research objective. Samples were taken for two seasons, winter (Nov 03 ?? Jan 03) and summer (Jun 04 ?? Aug 04), from each of the four treatment units: the inlet tank, equalization tank, aeration tank and the outfall tank. The population of aliphatic hydrocarbon degraders were enumerated and nutrient availability in the system were used to evaluate the effectiveness of on-going bioaugmentation and biostimulation. Monitoring of general effluent parameters was conducted to evaluate the treatment plant??s removal efficiency and to determine if effluent discharge was in compliance with the TCEQ permit. The aeration tank is an activated sludge system with no recycling. Hydrocarbon degraders are supplied at a constant rate with additional nutrient supplement. There was a significant decrease in the population of microbes that was originally fed to the system and the quantity resident in the aeration tank. Nutrient levels in the aeration tank were insufficient for the concentration of hydrocarbon degraders, even after the application of dog food as a biostimulant. The use of dog food is not recommended as a nutrient supplement. Adding dog food increases the nitrogen and phosphorus concentration in the aeration tank but the amount of carbon being added with the dog food increases the total chemical oxygen demand (COD) and biochemical oxygen demand (BOD). An increase in the concentration of total COD and BOD further increases the nitrogen and phosphorus requirement in the system. The main objective of supplying adequate nutrients to the hydrocarbon degraders would never be achieved as there would be an additional demand of nutrients to degrade the added carbon source. This research study was conducted to identify the drawbacks in the treatment plant which needs further investigation to improve efficiency.

Food service establishments that use onsite wastewater treatment systems are experiencing hydraulic and organic overloading of pretreatment systems and/or drain fields. Design guidelines for these systems are typically provided in State regulations and based on residential hydraulic applications. For the purposes of this research, hydraulic loading indicates the daily flow of water directed to the wastewater system. Organic loading refers to the composition of the wastewater as quantified by five-day biochemical oxygen demand (BOD5), total fats, oils and greases (FOG), and total suspended solids (TSS). The first part of this study included an analysis of the central tendencies of analytical data of four wastewater parameters from 28 restaurants representing a broad spectrum of restaurant types. Field sampling consisted of two sets of grab samples collected from each restaurant for six consecutive days at approximately the same time each day. These sets were collected approximately two weeks apart. The numerical data included BOD5, FOG, and TSS. The fourth parameter evaluated was daily flow. Data exploration and statistical analyses of the numerical data from the 28 restaurants was performed with the standard gamma probability distribution model in ExcelTM and used to determine inferences of the analytical data. The analysis shows higher hydraulic and organic values for restaurant wastewater than residential wastewater. The second part of the study included a statistical analysis of restaurant management practices and primary cuisine types and their influence on BOD5, FOG, TSS, and daily flow to determine if management practices and/or cuisine types may be influencing wastewater composition and flow. A self-reporting survey was utilized to collect management practice and cuisine type information. Survey response information and analytical data were entered into an ExcelTM spreadsheet and subsequently incorporated into SASTM statistical software for statistical analysis. Analysis indicated that the number of seats in a restaurant, use of self-serve salad bars, and primary cuisine types are statistically significant indicators of wastewater characteristics.

The water quality of rivers currently is seriously polluted in Taiwan for influencing drinking water quality, harming onto plants growth caused soil pollution problems by using river irrigation and harming the human health indirectly by contamination in river sediments. In this work, we will investigate the area of river water quality characteristics and pollution sources to solve effectively for the pollution problems in the river area of A-Gong-Den in Kaohsiung County. The source of the river area of this study is dam of A-Gong-Den. Their water quality is polluted majorly by the domestic and industrial wastewater. The dark red-color of river body was due to the effluent from those industrial factories. Heavy metals such as Zn, total Cr ions and conductivity were all over the water quality standard of irrigation uses. Thus, we will try to improve the color problems in this area of river by diagnostics method in five factories having wastewater treatment plants. The effective solution in management and controlling will be discussed. We investigate the treatment facilities and performance evaluation in five industrial plants. We found the wastewater treatment and operation technology should be done and elevated in some factories. Importantly, the marked signs in pipelines in wastewater treatment were not clear and operated under not normal conditions. The EPA in county should send officers for checking the operations of the wastewater treatment plants in listings with a normal period for once.

The water sector is responsible for a significant portion of energy use. Energy is required for water treatment, water distribution, wastewater collection and wastewater treatment. There is significant benefit to water utilities that can be gained by understanding how much energy, what type of energy, and at what time of day energy is being used. The Austin Water Utility (AWU) is a useful testbed for examining the energy use for each specific step of the process due to the availability of data and the fact that the majority of Texas (both in terms of population and land area) is serviced by a single electric grid. This research examines the type and quantity of energy used by AWU. From an electricity supply perspective, electric utilities work year round to ensure that there is enough electricity in their generation portfolios to meet the high loads that their customers demand, and to assure that the electric distribution grid is capable of providing the transmission requirements of that electricity. System peak demand is the largest amount of electricity consumed by a utility's customers at any given time. Therefore electric utilities, such as Austin Energy, create and market their energy efficiency programs to help reduce this peak and avoid the need to build new generation capacity which can be expensive. Because AWU is one of Austin Energy's largest customers, AWU's ability to shift its energy use from on-peak to mid-peak and off-peak time periods can contribute towards reducing the peak, and can help avoid the need for new generation capacity. This analysis finds that AWU can reduce its electricity demand during peak periods by making use of reservoir capacity, i.e. by filling its reservoirs prior to peak time and draining them during peak periods. This proposed pumping schedule could save AWU up to 29% of its monthly electricity costs under current Austin Energy time-of-use rate (as opposed to flat rate) structures at the specific pump station analyzed as part of this research. Together, state-wide water utilities provide even more opportunities for the interconnected Electric Reliability Council of Texas' (ERCOTs) grid that are also evaluated in this research. / text

In Ghana, wastewater is frequently used as a source of irrigation water for crops in urban areas, due to water scarcity and an increasing population growth. The water contains high amounts of nutrients, but also other unwanted constituents such as heavy metals, pathogens and pharmaceutical residues and is a potential health risk for the consumers. This study aimed to determine the status of pharmaceutical pollution in irrigation water used in Chirapatre Estates, a suburb to Kumasi, Ghana. Chirapatre Estates is located on a hill sloping towards a stream, with a network of sewer lines connected to a Waste Stabilization Pond (WSP). Problems regarding disposal of pharmaceutical waste, frequently used medications in the area and water quality of irrigation water was analyzed through interviews and water analysis. The interviews were made with households, farmers and pharmacies and the water samples were collected at farms and the maturation pond, the final treatment in the WSP. The analysis focused on the water quality parameters; pH, Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), total phosphorus, phosphate, total nitrogen and nitrate. The empirical study showed high use of malaria treatment medication and paracetamol for adults as well as children. No instructions of disposal of unused medications were expressed through the pharmacy or by the government, causing the majority of the inhabitants to dispose their leftovers in the trash. One can speculate that there might be a possible risk of finding some pharmaceutical residues in the aquatic environment, especially for the types of pharmaceuticals that can be persistent. The results indicated that the water quality from the WSP and at the farming sites was acceptable when compared to the Ghana Environmental Protection Agency (EPA) guidelines, except for TSS and total phosphorus. Further treatment of the water is still suggested, since adjacent farms use the water frequently and the EPA guidelines are not fulfilled. Future studies are recommended to establish the pharmaceutical residues present in the stream water.

The anaerobic oxidation of ammonium (anammox) with nitrite as electron acceptor is a microbial process that generates nitrogen gas as main final product. After being discovered in the Netherlands in the 1990s, anammox has been applied in state-of-the-art biotechnologies for the removal of N pollution from ammonium rich wastewaters. The anammox process offers significant advantages over traditional nitrification-denitrification based processes. Since anammox does not need elemental oxygen, it allows for important savings in aeration. Furthermore, due to the autotrophic nature of the bacteria, anammox does not require external addition of electron donor, often needed in systems with post-denitrification. Although the anammox bacteria have high specific activity, they are slow growing, with doubling times that can range from 10 to 25 d. Therefore, in case of a toxic event causing the death of the biomass, a long recovery period will be required to reestablish full treatment capacity. The purpose of this work is to investigate the inhibition of anammox bacteria by compounds commonly found in wastewaters, including substrates, intermediates and products of the anammox reaction. Among common wastewater constituents, sulfide was shown to be especially harmful, causing complete inhibition of anammox activity at concentrations as low as 11 mg H₂S L⁻¹. Dissolved oxygen was moderately toxic with a 50% inhibiting concentration of 2.3 and 3.8 mg L⁻¹ to granular and suspended anammox cultures, respectively. Among the various compounds involved in the anammox reaction, special attention was paid to nitrite. Numerous literature reports have indicated inhibition of anammox bacteria by its terminal electron acceptor. However to date, there is no consensus explanation as to the mechanism of nitrite inhibition nor on how the inhibition is impacted by variations in the physiological status of anammox cells. The mechanisms of anammox inhibition by nitrite were thoroughly investigated in batch and continuous experiments of this dissertation. The results of this work demonstrate that conditions hindering generation of metabolic energy have a detrimental effect on the tolerance of anammox cells to toxic levels of nitrite. The absence of ammonium during events of nitrite exposure was shown to exacerbate its toxic effect. As a result of nitrite inhibition, nitric oxide, an intermediate of the anammox reaction, accumulated in the head space of the batch experiments. Moreover, nitrite inhibition was enhanced at the lowest range of pH tested (6.4-7.2), while same nitrite concentrations caused no inhibition under mildly alkaline conditions (7.5-7.8). Although other authors have relied on the classic concept that undissociated nitrous acid is the species responsible for the inhibition, the results in this work indicate that the pH affects the inhibitory effect of nitrite, irrespective of the free nitrous acid concentration. Nitrite stress triggered an active response of the anammox bacteria, which temporarily increased their ATP content to mitigate the inhibition. Additionally, starvation of anammox microorganisms, caused during storage or by sustained underloading of bioreactors, was found to limit the capacity of the bacteria to tolerate exposure to nitrite. The results of this dissertation indicate that the tolerance of anammox bacteria to NO₂⁻ inhibition relies on limiting its accumulation in sensitive regions of the cell. Active metabolism in presence of NH₄⁺ allows for active consumption of NO₂⁻, avoiding accumulation of toxic intracellular NO₂⁻ concentrations. Furthermore, secondary active transport proteins may be used by anammox bacteria to translocate nitrite to non-sensitive compartments. Nitrite active transport relies on a proton motive force. Therefore, conditions such as low pH (below 7.4) or absence of energy sources, which may disturb the maintenance of the intracellular proton gradient, will increase the sensitivity of anammox cells to NO₂⁻ inhibition. Strategies for the operation and control of anammox bioreactors must be designed to avoid exposure of the biomass to nitrite under the absence of ammonium, low pH or after periods of starvation.

Nitrate is a common groundwater contaminant. Due to adverse health effects, waters above the Maximum Contaminant Level (MCL) of 10 mg NO3-N/L or 0.71 mmols/L, are banned from domestic consumption by the EPA. Studies have measured elevated nitrate concentrations in arid land soils and groundwater around the world. These elevated concentrations could be detrimental to the environment and to human health. Thus, it is important to consider the different sources and processes affecting nitrate concentrations Here, a novel triple isotope system approach was employed, coupling δ17O with δ18O and δ15N of nitrate to determine the sources (atmospheric, terrestrial, fertilizer, wastewater) and removal processes influencing nitrate concentrations in the Tucson basin groundwater system. Results show low groundwater nitrate concentrations (0.2 mmols/L) where wastewater was not a predominant source of water, versus high concentrations (1 mmols/L) above the MCL in groundwaters where wastewater was the dominant water source. Furthermore, groundwater up to 1.6 Km away from the wastewater stream was contaminated with effluent recharge waters. In addition, denitrification was inferred from δ18O and δ15N data with this inference reinforced by δ17O data and δ15N enrichments up to 26. Finally, low atmospheric nitrate was measured in groundwater, representing up to 6% of total nitrate. The triple isotope approach studied here is ideal for determining the proportion of atmospheric nitrate versus other terrestrial nitrate sources and the significance of nitrate removal processes.

Wastewater reclamation and reuse is imperative in water-starved areas such as the southwestern United States. In the Tucson Active Management Area, a geographic region defined for the purpose of groundwater management, the total demand for water already exceeds the available water supply, which consists of renewable ground water and the regional entitlement to Central Arizona Project water. Thus, the regional demand cannot be satisfied without resorting to groundwater mining unless water is reclaimed for local beneficial use. Less certain are the acceptable uses for reclaimed water and the nature of use-dependent treatments or water quality requirements that will protect human and ecological health. Disruption of thyroid-mediated actions is among the possible risks from chronic exposure to environmental contaminants. Endocrine disrupting compounds are generally of greater concern in this context than other trace contaminants because of the very low concentrations at which hormones induce physiological responses. Accordingly, a sensitive nuclear-based bioassay system was developed in order to evaluate environmental samples. A luciferase-reporter construct and the human thyroid receptor β (TR-β) construct in the human hepatoma cell line (HepG2) and human medulloblastoma cells (TE671) was evaluated for sensitivity. The transfected cells were exposed to the thyroid hormone, T3, in order to establish a lower thyroid hormone detection limit for the new bioassay procedure. The assay was then applied to environmental samples containing organics concentrated from final effluent derived from a conventional secondary wastewater treatment plant. The effluent samples activated thyroid receptor-mediated transcription. Also in this study, a two-dimensional gel electrophoresis (2D-DIGE) was used as an in vitro bioassay to look for wastewater related alteration of cellular protein expression in the human breast cancer cell T47D. Steps in this bioassay include the one-dimensional separation of proteins by isoelectric focusing followed by orthogonal electrophoresis to isolate the proteins. The consistency of test response was examined for wastewater-dependent up- or down-regulation of protein expression. Some proteins that were upregulated were preliminarily identified via mass spectrometry. Here, the procedure is used to provide direct information regarding the probable effects of residual hormones in treated wastewater on the activities of human, estrogen-responsive cells in cell culture.

The aim of this project was to look into ten small sewer systems in the municipality of Laholm, in Sweden, in order to work out common assessment grounds for them. The sizes of the systems for purification of wastewater were within the range of 25 to 2000 population equivalents. Our method was to study literature, the laws and regulations applicable and the files at the municipality. The conclusion is that every sewer system is different and every situation is unique. We concluded that based on laws and assessment grounds sewer systems equal in size and pollution load ought to have similar demands attached to them. Four of the sewer systems are in need of adjustments or renovations. One sewer system in particular, Hishult, needs large-scale adjustments and improvements to live up to the demands attached to it. This sewer system is where we think the focus from the municipality ought to be the strongest, based on the result from this review. It requires most effort, time and money, to get it running with least amount of environmental impact. We also suggested levels for degree of purification for all of the sewer systems. As a common ground we set the demands equal to the ones for private sewer systems. The demand for purification of phosphorus was adjusted to if the system was equipped with chemical precipitation or not. Subsurface filters are left without measures. The focus of demands on systems of that kind is set to new construction or full scale restoration.

Wastewater microbial flocs can protect microorganisms from inactivation by UV light. This effect is detected as tailing at high UV doses in the UV dose response curve. A double-layer structure composed of an inner compact core surrounded by a loose outer layer was proposed by earlier studies to describe UV resistance of microbial flocs. Due to limited oxygen diffusion into the compact cores, the UV inactivation of compact cores and microbial flocs under anaerobic conditions needed to be addressed. The UV disinfection kinetics under anaerobic culturing condition was nearly identical to that of the aerobic study. Moreover, the role of iron concentration on the differences in the UV inactivation kinetics of flocs and cores was assessed. The increase in UV absorbance of floc material due to iron addition could dominate the UV disinfection kinetics of flocs and cores such that they exhibited similar UV disinfection kinetics.