With increasing population comes the concern for waste disposal. The absence of sanitary disposal methods has left most city residents with open landfills as their only source of waste disposal. The resulting leachate formed from the decomposition of these waste materials is highly polluting and finds its way to the underground water supply. The study investigated the effects of open landfill sites on the underground water quality by examining the physical and chemical properties of underground water in hand-dug wells around the Solous landfill sites in Igando, Alimosho Local Government Area of Lagos State. Solous landfill is the second largest landfill by landmass and volume of waste in Lagos State. Systematic random sampling was used for data gathering. Eighteen hand-dug wells were sampled at increasing distances from the landfill site. Physical, chemical and microbiological parameters were analysed at the Lagos State Environmental Protection Agency (LASEPA). Soil samples were also taken from both the A (0 – 30cm) and B (30 – 60cm) horizons of the water sampling points to determine the soil texture (silt, clay and loamy composition) and to show the impact of soil texture on ground water quality within the sampled area. The level of contamination of groundwater was also determined using the Contamination Index method. The results showed high degree of conformance with W.H.O standard with respect to the microbiological properties of the sampled groundwater. However, coliform tests indicated the potential presence of pathogens. Of the seven (7) physical parameters tested, conductivity was higher in one sample. The study of chemical properties from the eighteen wells showed five (5) parameters (dissolved oxygen, total alkalinity, iron, lead, nitrates and copper) above W.H.O limits in some samples. The water may therefore not be safe for human consumption and there is a serious need to monitor the groundwater quality in the area. The level of contamination of groundwater was also determined using the Contamination Index method. Areas of high and medium contamination were discovered. There was no area with low contamination level in the area sampled. Contamination levels were mapped to show the exact levels of contamination in the study area. The results of the soil analysis showed that the study area had soil that was mostly sandy in nature which may suggest an increase in parameters over time with significant health implications for the people who depend on surrounding wells for domestic use. The study also showed no significant variation in water quality with increasing distance from the dump site. Findings also indicated that the water around Solous 1 was of better quality for domestic use than groundwater around Solous 2 and 3 due to temporal reduction of contaminant concentration. There is therefore a need for adequate and proper planning, design and construction, and strategic management disposal of waste, as well as the implementation of a better sustainable environmental sanitation practice. / Environmental Sciences / M. Sc. (Environmental Science)

An experimental study was carried out to evaluate the performance of pilot scale constructed wetlands for the treatment of domestic wastewater in Addis Ababa, Ethiopia. Three parallel sets of constructed wetlands; consisting of one Horizontal Flow (HF), one Vertical Flow (VF) and one hybrid of HF and VFconstructed in series were built in Addis Ababa. The wetland systems had identical wetland fill media and macrophytes but with different wastewater flow types. The total surface area of the wetland systems was 72 m2 /24 m2 for each/ and designed to treat 3.15 m3 of domestic wastewater per day. Triplicate grab samples were taken from the influent and effluents every 15 days for one year and analyzed within 24 hours. Temperature, pH, DO and EC were measured onsite and the nutrient content of macrophytes was determined twice during the monitoring period. During the first 12 months monitoring period, the average removal efficiencies of the HFCW, VFCW and hybrid CW were: BOD (89.1%, 92.2% and 93.4%), COD (80.6%, 82.1% and 84.0%), TSS (89.1, 83.8% and 84.7%), NH4 + (58.6%, 66.2% and 65.4%), NO3 - (64.0%, 71.5% and 73.5%), TN (49.1%, 54.9% and 58.7%), PO4 3- (45.4%, 50.3% and 48.4%), TP (58.0%, 51.7% and 54.4%) and FC (98.6%, 96.6% and 96.5%), respectively. The hybrid system showed relatively higher removal efficiencies for most pollutants. Again, the wetland systems showed relatively higher percent reduction during the dry seasons /from Dec - May/. The areal removal rate constants of BOD5, TN, PO4 3- and TP were higher than the literature values while the values of COD and TSS were lower compared to the literature values. Concerning the nutrient content of the wetland plant, the average TN contents of the below-ground and above-ground plant part were 1.56% and 2.27% for the HFCW, 1.75% and 2.74% for the VFCW and 1.80% and 2.63% for the hybrid system, respectively. Meanwhile, the average TP contents of the belowground and above-ground plant part were 0.139% and 0.064% for the HFCW, 0.167% and 0.067% for the VFCW and 0.115% and 0.065% for the hybrid systems, respectively. In general, the results showed that properly designed constructed wetland systems could be used as effective wastewater treatment method in Ethiopia. / Environmental Sciences / Ph. D. (Environmental Sciences)

Includes bibliographical references (leaves 136-154) Aims to determine the effects of an outfall discharging secondarily treated wastewater effluent on benthic communities at Christies Beach with the specific objectives of: characterising the physical, biological and chemical environment of Gulf St Vincent and the study area region; ascertaining the extent to which effluent outfall has affected the macrobenthic infaunal community structure; characterising the structure of macrobenthic infaunal communities in the near shore water of the Adelaide metropolitan coast; and, determining the functional response through measurements of sediment community respiration to these changes.

Includes bibliographical references (leaves 136-154) / xvii, 171 leaves ; ill. (some col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Aims to determine the effects of an outfall discharging secondarily treated wastewater effluent on benthic communities at Christies Beach with the specific objectives of: characterising the physical, biological and chemical environment of Gulf St Vincent and the study area region; ascertaining the extent to which effluent outfall has affected the macrobenthic infaunal community structure; characterising the structure of macrobenthic infaunal communities in the near shore water of the Adelaide metropolitan coast; and, determining the functional response through measurements of sediment community respiration to these changes. / Thesis (Ph.D.)--University of Adelaide, Dept. of Environmental Biology, 2001

From the Proceedings of the 1972 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - May 5-6, 1972, Prescott, Arizona / High concentrations of nitrate have been found in water samples from irrigation wells north of the Tucson Arizona sewage treatment plant. The plant, which had primary treatment prior to 1951, produced 2,800 acre-feet of effluent in 1940, 4,600 acre-feet in 1950, 16,300 acre-feet in 1960, and 33,000 acre-feet in 1970. Large amounts of treated effluent recharge the groundwater system north of the plant. Sources of nitrate contamination beside sewage effluent may be sewage lagoons, sanitary landfills, meat packing and dairy effluent, septic tanks, and agricultural runoff. Sewage effluent is considered to be the primary source of nitrate contamination in the area. Geologic and flow net analysis indicate that aquifer conditions minimize the effects of sewage effluent contamination. Chloride and nitrate migration appears to be similar in the aquifer. Large-capacity wells were sampled to reflect regional conditions, and chemical hydrographs of chloride and nitrate were analyzed. The seasonal nature of these hydrographs patterns depend on total nitrogen in sewage effluent. Management alternatives are suggested to decrease nitrate pollution by sewage effluent.

From the Proceedings of the 1974 Meetings of the Arizona Section - American Water Resources Assn. and the Hydrology Section - Arizona Academy of Science - April 19-20, 1974, Flagstaff, Arizona / The 14.6 miles of the Colorado River bounded by Parker Dam and Headgate Rock Dam has been referred to as the Parker Strip. This river reach has become a high use recreation area during the past decade with 4,000 permanent residents and as many as 120,000 water enthusiasts on long weekends. The riparian area of the river is heavily clustered with mobile homes, marinas and public beaches. The means of sewage disposal is exclusively via septic tanks. Recent surveys by the Environmental Protection Agency, Arizona State Department of Public Health and the University of Arizona have localized surface water bacteria levels that may indicate a developing groundwater problem. The geohydrology of the area indicates that the septic tanks are located in Post -Pliocene Colorado River deposits. The deposits are quite thin and relatively narrow. Since the deposits are locally derived sands and gravels, the horizontal hydraulic conductivities are such that a relatively short flow time to the river may result. Intensive evaluation of the degradation of the water quality in these deposits is needed to determine if the ground water supply was jeopardized by septic tank systems.

It is projected that by 2025 three-quarters of the world’s population will live in the coastal zone. This is an alarming statistic, with a consequently significant impact on small coastal towns and the adjacent marine environments. Developing communities within the coastal zone of South Africa have proved to be a significant pollution source of storm water. Studies have shown that storm water that is deposited in the ocean will be trapped in the near shore marine environment causing poor seawater quality over a large distance. Furthermore, this can pose a significant threat to the health of recreational users and important marine ecosystems. In Jeffreys Bay storm water quality is thought to pose a threat to the maintenance of the international Blue Flag status for its beach. The aim of the current project was to investigate the main sources of storm water and subsequent marine pollution at Jeffreys Bay and to develop an appropriate management strategy using the integrated environmental management framework. In order to achieve this objective, it was also necessary to determine the current quality of water at various points within the catchment and near shore marine environment. Even though the storm water was found to be severely contaminated no evidence existed for a negative impact on the marine environment. None the less, a precautionary approach was adopted and a risk assessment employed in order to consider potential impacts on the marine and aquatic environment, human health and socio-economic welfare within the town. Significant sources of storm water contamination included grey water, domestic solid waste disposal and informal ablution. These significant aspects were investigated further and it was found that solid waste management in the catchment was poor with significant quantities of waste, primarily (76%) from domestic sources, being disposed of illegally. A study of sanitation management showed inadequacies where up to 58% of the residents from the informal settlements disposed of their grey water into open spaces. The ratio of residents to toilets in these areas was 28:1, therefore supporting the outcome of the risk assessment. Due to the fact that all the significant aspects were related to anthropogenic waste, an integrated waste management plan (IWMP) was developed that would not only facilitate the reduction of pollution of storm water, but would also allow for sustainable community-based development.

With increasing population comes the concern for waste disposal. The absence of sanitary disposal methods has left most city residents with open landfills as their only source of waste disposal. The resulting leachate formed from the decomposition of these waste materials is highly polluting and finds its way to the underground water supply. The study investigated the effects of open landfill sites on the underground water quality by examining the physical and chemical properties of underground water in hand-dug wells around the Solous landfill sites in Igando, Alimosho Local Government Area of Lagos State. Solous landfill is the second largest landfill by landmass and volume of waste in Lagos State. Systematic random sampling was used for data gathering. Eighteen hand-dug wells were sampled at increasing distances from the landfill site. Physical, chemical and microbiological parameters were analysed at the Lagos State Environmental Protection Agency (LASEPA). Soil samples were also taken from both the A (0 – 30cm) and B (30 – 60cm) horizons of the water sampling points to determine the soil texture (silt, clay and loamy composition) and to show the impact of soil texture on ground water quality within the sampled area. The level of contamination of groundwater was also determined using the Contamination Index method. The results showed high degree of conformance with W.H.O standard with respect to the microbiological properties of the sampled groundwater. However, coliform tests indicated the potential presence of pathogens. Of the seven (7) physical parameters tested, conductivity was higher in one sample. The study of chemical properties from the eighteen wells showed five (5) parameters (dissolved oxygen, total alkalinity, iron, lead, nitrates and copper) above W.H.O limits in some samples. The water may therefore not be safe for human consumption and there is a serious need to monitor the groundwater quality in the area. The level of contamination of groundwater was also determined using the Contamination Index method. Areas of high and medium contamination were discovered. There was no area with low contamination level in the area sampled. Contamination levels were mapped to show the exact levels of contamination in the study area. The results of the soil analysis showed that the study area had soil that was mostly sandy in nature which may suggest an increase in parameters over time with significant health implications for the people who depend on surrounding wells for domestic use. The study also showed no significant variation in water quality with increasing distance from the dump site. Findings also indicated that the water around Solous 1 was of better quality for domestic use than groundwater around Solous 2 and 3 due to temporal reduction of contaminant concentration. There is therefore a need for adequate and proper planning, design and construction, and strategic management disposal of waste, as well as the implementation of a better sustainable environmental sanitation practice. / Environmental Sciences / M. Sc. (Environmental Science)

This thesis deals with the design and static assessment of a concrete part of a sewage treatment plant. Specifically, the calculation and assessment of the base plate, external walls, internal walls and ceiling slabs, elaboration of shape and reinforcement drawings of selected structural element. The concrete part of the Sewage disposal plant is all below ground level. Static system and the calculation of internal forces was carried out in Scia Engineer 2011 - student version.

MENVSC / Department of Ecology and Resource Management / The main objective of the study was to investigate the effectiveness of municipal solid waste management system, its potential implication in Vhembe District Municipality, South Africa and to recommend strategies for effective management of municipal solid waste in the district. To achieve this, structured questionnaires, interviews, field observations and focus group discussions were used to collect primary data within the district. The study focused on the four local municipalities: Makhado, Thulamela, Musina and Collins Chabane. Desktop study was also undertaken to gather secondary data by reviewing journals, technical reports, books and articles. The study adopted a mixed method approach comprising of triangulation of qualitative and quantitative design. The target groups of the study were selected through purposive sampling. The respondents in the study were 21 officials from local municipalities including directors, waste managers, superintendents, landfill supervisor and interns. Data was collected using focus group interviews and questionnaires and analysed using descriptive statistics which involve the presentation of numerical facts, or data, in either tables or graphs form. Municipalities in the district are producing a considerable amount of solid waste. Municipalities do not adhere to the existing guidelines on waste minimization at source, for example; they do not have zero waste strategy (3R) reduce, reuse and recycle, which is the highest priority of the National Waste Management Policy. Lack of the application of existing waste management policy leads to large amount of solid waste eventually ending up in landfill sites. The study recommends to municipalities to develop operational and monitoring waste management plans which will create continuous improvement on waste management. In the district, it was observed that the bulk of waste generated per month within municipalities is general waste comprising 64%, as compared to garden waste and building rubbles. There are no equipment and programs in place by municipalities to encourage waste separation at source, for example, municipalities do not have household‟s recyclable receptacles to encourage separation at source. Municipalities do not have weighbridge to quantify waste entering the site. It was observed that Thulamela and Collins Chabane Local municipalities create compost from garden waste received at the landfill sites, whereas Musina and Makhado Local Municipalities do not create compost from garden waste. Garden waste is dumped and compacted with other waste materials in the landfills. All municipalities should create compost from garden waste received at the landfill sites as it helps to extend the life span of the landfills because it v reduces the amount of waste to the landfill. There is lack of prioritization within municipalities, for example, in Makhado Local Municipality, when the new financial start, budget is allocated to other proposed projects by councilors as they consider waste management projects not a priority. It was observed that within the district, there is high level of illegal dumping in catchment areas and open spaces especially at Musina Local Municipality. Musina Local Municipality is using a quarry as disposal site which was not lined and it has led to contamination of underground water by leachate, whereas Thulamela, Collins Chabane and Makhado Local Municipalities are using lined landfill sites to avoid contamination of underground water. The available vehicles within the municipalities are not enough to meet the demand and some of them are too old, for example, tractors and trucks used by Makhado Local Municipality are 20 years old and they often breakdown, whereas Thulamela, Collins Chabane and Musina Local Municipalities are not using old vehicles as they auctioned old vehicles and bought new ones. Vhembe District Municipality should manage waste in accordance to the new approach of source separation, waste reduction, reuse and recycling by developing environmental awareness programmes supported by the placement of the recyclable receptacles at strategic points to collect recyclable materials which will reduce large amount of waste which eventually ends up in landfills. The study recommends that municipalities should have law enforcement structure which will create and enforce the laws/policies as it helps municipalities to implement effective waste management system and monitoring structure to monitor prioritization and budget allocation to avoid any wastage. Municipalities should have landfill monitoring committees to facilitate the compliance on the development and operation of the landfills to avoid the use of quarry as landfill sites. / NRF