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Stakeholder participation in surface water and groundwater quality management in the Waterberg area: Limpopo Province, South AfricaCornelus, Lesley-Ann Jolene January 2018 (has links)
A Research Report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science, 2018 / The aim of this research was to assess the status of water quality in a selected area of the Waterberg over a twenty-year period and to gain insight into the perceptions of stakeholders about water management. The objectives were met through the comparison of historical water quality variable records for various water uses, by measuring the level of stakeholder commitment in water quality measurement and verifying a relationship between the two approaches.
This study focuses on measuring the extent of different stakeholders’ involvement in the management and decision-making processes of water quality in the Waterberg region of Limpopo province, which is encouraged by the formulation of South African policies. The specific area of interest is in the north-western part of the Waterberg. There are three distinct settlements, Lephalale, Marapong and Steenbokpan, located in the Lephalale Local Municipality. Close by are major industrial and mining activities from Eskom’s Matimba and Medupi power stations, and Exxaro’s Grootegeluk Coal Mine.
To address the specific research questions and objectives for this study, two approaches were necessary: A quantitative approach that required surface water and groundwater data from 1995 to 2015, to determine the quality of water, and a qualitative approach that comprised of the distribution of 20 questionnaires in the residential areas, and 15/20 successful pre-selected individual interviews, to assess the different levels of stakeholder participation. Each approach presented its own challenges. For example, the water quality data provided were incomplete, which created limitations in the interpretation and during the questionnaire distribution, time constraints and language preferences, though anticipated amongst different social groups, there was difficulty communicating the concept of the study. Also, during the planning phase of selecting interviewees, there was a lack of interest in the study from environmental consultants, who are vital role players in the environmental status of the area.
The water quality data indicated that pH levels in the surface water sites have remained steady and are not significantly different from one another. The results from the one groundwater site, reveals that there is a significant difference between the pH levels of surface water and groundwater which is to be expected. The results also suggest that the high concentration of ammonium, phosphate and nitrate midstream in the Mokolo River are related to the waste water being discharged mid-stream into the river via a pipeline. The high concentrations of sodium and potassium in the groundwater site are linked to the interaction time with the surrounding geology and the overall EC levels correspond with the fluxes in sodium in the groundwater site
resulting in the significant difference in EC between the surface water and the groundwater sites. No data were available for the midstream site.
The questionnaire results indicate that there’s limited stakeholder involvement in water quality management from participants in Steenbokpan and Marapong, which are socio-economically disadvantaged areas, when compared with Lephalale, a more affluent area. In contrast to Lephalale, Marapong and Steenbokpan residents are less educated, have higher unemployment numbers, and have restricted access to water related information, and electricity, water and sanitation services. In the overall area, there is also a 30% unawareness amongst general water users about the topic of water pollution, but again it is mostly from participants in Steenbokpan and Marapong.
The interview results signified a higher level of stakeholder involvement in water quality management from individuals in influential positions. This, however, does not mean that water related issues in the area are adequately addressed. Interviewees revealed that there is a lack of funding, skills, infrastructure, manpower and competence. There is also an apparent inequality with regards to water access to informal settlements, farmers and rural villages. Additionally, there is a high level of dependency on Eskom and Exxaro, rather than the local municipality, to provide its water users with proper water services. The dependency on Eskom and Exxaro is largely due to their high level of influential development. Improvements and maintenance on basic service from these structures to the surrounding communities form part of their offset programmes to continue major development in the area.
Due to the large difference of the qualitative and quantitative approaches, it was difficult to prove how one supports the other, even though, on its own, both are crucial components in water quality management practices. Even though the water quality data provide more reliable support on the condition of surface- and groundwater in the Waterberg, the social aspect (partially revealed through the subjective view of the general users who completed the questionnaire) is required to determine the community’s relationship with water use and to identify management practices through stakeholders responsible for them. / XL2018
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Water and Air Quality Performance of a Reciprocating Biofilter Treating Dairy WastewaterHenneman, Seppi Matthew 01 March 2011 (has links) (PDF)
ABSTRACT
Water and Air Quality Performance of a Reciprocating
Biofilter Treating Dairy Wastewater
Seppi Matthew Henneman
Agricultural non-point source pollution is the leading water quality problem in surface water and the second leading problem in ground water in the US. Among the contaminants, nutrients (such as nitrogen, phosphorus, potassium) can be transported from agricultural fields when cropland is not managed properly. In California, dairy manure application to cropland has become tightly regulated with the goal of decreasing such nutrient pollution. Dairies unable to balance their manure nutrient supply with cropland application area may benefit from a nitrogen removal technology. One such technology is the reciprocating biofilter, known as the ReCip® technology. A pilot-scale ReCip® unit was installed at the Cal Poly dairy to evaluate its treatment efficacy, in particular for nitrogen removal, when treating wastewater from flush dairies. This pilot-scale system was the first application of the ReCip® technology to dairy wastewater, and recently it was found to be effective for removal of ammonium, total nitrogen, and biochemical oxygen demand (BOD). In the ReCip®, wastewater is repeatedly pumped back and forth between two gravel-filled basins. This reciprocation creates two treatment environments: an aerobic environment, which promotes reactions such as nitrification and BOD oxidation, and an anoxic/anaerobic environment, which promotes reactions such as denitrification of nitrate into nitrogen gas and methanogenesis. At Cal Poly, the ReCip® treated storage lagoon water, and ReCip® effluent containing nitrate was returned to the lagoon, possibly contributing to odor control. Emission of air pollutants is a concern about dairy waste in general (volatile organic compounds, hydrogen sulfide, methane, etc.) and for nitrification-denitrification systems in particular (nitrous oxide).
In the present work, the first detailed air emission study was conducted on ReCip®. Emissions of air pollutants were measured with flux chambers during different seasons, and, simultaneously, the water quality within the pore volume of the gravel beds was measured to explore whether pore water quality correlated to air emissions. These air emissions studies were performed within a yearlong study of overall ReCip® treatment performance. Water quality constituents measured were pH, alkalinity, temperature, dissolved oxygen (DO), total ammonia nitrogen (TAN), soluble nitrogen, soluble non-purgeable organic carbon, nitrite, and nitrate. During the submerged phase of the reciprocation cycle, pore water DO generally declined from 1-2 mg/L to <0.1 mg/L, while TAN declined and nitrate accumulated, although total nitrogen also declined due to denitrification. The extent of denitrification was correlated to influent BOD loading. The average removals by the ReCip® were 93% TAN, 61% CBOD5, 74% TKN, and 57% TSS. A simple CBOD5 removal model was developed that described and predicted CBOD5 removal in the system.
Key air pollutants emitted by the ReCip® and their annual mean concentrations were nitrous oxide (0.74 ppm), ammonia (0.15 ppm), and methane (3.85 ppm). The air emission potential of the lagoon water influent was compared to that of the ReCip® effluent. The decreases in emission potential were 82% for ammonia, 93% for methane, and 99% for hydrogen sulfide. The average masses emitted (g emitted/kg loaded into system) by the ReCip® were 1.7 g N2O/kg N, 0.15 g NH3/kg N, 2.1 g CH4/kg CBOD5, 1.0 g ethanol/kg CBOD5,and 0.004 g H2S/kg CBOD5.
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Analysis of disinfection by products in drinking water by solid phase extractionSexton, Diane Lynne 12 September 2009 (has links)
The objectives of this research were to develop a broad spectrum method for the extraction, concentration, and analysis of drinking water disinfection by products using solid phase extraction (SPE), and to determine if this method had lower detection limits and less variability than the proposed liquid-liquid extraction method, EPA Method 551. The disinfection by products investigated were halogenated nitriles, ketones, and aldehydes. The SPE method extracted and concentrated samples using the C-18 Empore Extraction Disks, and desorbed the analytes with methyl-tert-butyl ether (MTBE) as a solvent. The results showed that with the SPE method the recoveries were low (0-50%) for most compounds, and the limit of detection (LOD) values were in the range of 0.2 to 50 ug/L, which were much higher than those for EPA Method 551. The variability was also higher than for EPA Method 551. The SPE method also appeared to be concentration dependent; the recoveries decreased as analyte concentration increased. Highly saline conditions (250 g/L NaCl) resulted in low recoveries and concentration dependencies for some compounds. Even though the SPE method was easier and faster, the lower method detection limit (MDL) values and lower variability made Method 551 more preferable. Further analysis of the SPE method using a new cyclohexyl disk was also recommended. / Master of Science
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Report on the investigation of the removal of iodine (I¹³¹) and strontium (Sr⁸⁹) from water by ion exchange resinsFriend, Albert Gallatin January 1952 (has links)
Master of Science
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An assessment of a liquid-liquid extraction procedure for the gas chromatographic analysis of chloroform in algal mediaPerry, Kimberly Jean January 1979 (has links)
The purpose of this study was to evaluate the effects of several factors which might alter the analysis of chloroform in aqueous samples by the liquid-liquid extraction (LLE) method developed by Glaze at North Texas State University. A Bendix gas chromatograph (GC) was used. The factors examined were the effect of the ionic strength of the sample on the extraction method, the relative extraction efficiency when three pentane-to-sample ratios were used, the change in the response of the GC to a set of samples during a several hours lengthy analysis, the precision of the data obtained by the analysis procedure, and the precision of analyses of aqueous chloroform standards made from one set of secondary standards. These factors were examined to aid in the development in this laboratory of an analysis program to study the role of algal extracellular metabolites as trihaloomethanes precursors.
Ionic strength up to 0.0116 (strengths of algal media) did not affect the results. Few differences in the extent of linearity or extraction efficiency were detected when pentane-to-sample ratios of 1:1, 2:1, or 1:2 were used. The extraction efficiencies of the three ratios deviated 11 percent of their mean, with four values not included. The GC's response to a set of samples analyzed at the beginning and end of a nine-to-twelve hour experiment may change significantly. Standards prepared in pentane did not change during the test period. Four replicate analyses of the same sample were found to be highly precise. / Master of Science
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Comparison of ion chromatography and flow injection analysis methods for monitoring chlorite and chlorate ions in drinking waterLedder, Tracey 17 March 2010 (has links)
Up-coming regulations on chlorine dioxide in drinking water treatment require low level measurement of chlorite ion (CI0₂-) and chlorate ion (CI0₃-). This research investigated analysis of CI0₂- and CI0₃-; in drinking water by flow injection analysis with iodometric detection (FIA) and ion chromatography with conductivity detection (IC).
Both the FIA and IC methods were accurate for the determination of CIO₂-; and CIO₃-; in reagent water. The IC method was accurate in drinking water, however, FIA responded to chloramines and other oxidants present in drinking water causing inaccurate analysis of CIO₂-; and CIO₃-; by FIA.
The two IC eluants investigated, a carbonate/bicarbonate mixture and a borate/boric acid mixture, performed well. By taking advantage of the slightly different separation abilities of each eluant, the IC method can be modified to maximize resolution of CIO₂-; and CIO₃-; in different drinking water matrices.
Chlorite was unstable in chlorinated drinking water but was stable for up to three days when sodium oxalate was added and stable up to eighteen days when ethylene diamine was added as a preservative. Chlorate was stable in drinking water for up to eighteen days with or without a preservative.
The propagation of errors method for determining detection limits yielded limits of detection for CIO₂- (mg/L) of 0.05 for FIA, 0.03 for the IC carbonate eluant and 0.01 for the IC borate eluant. For CIO₃- the limits of detection (mg/L) were 0.24 for FIA; 0.11 for the IC carbonate eluant and 0.02 for the borate eluant. / Master of Science
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Optimization and verification of changes made to US-EPA 1623 Method to analyse for the presence of Cryptosporidium and Giardia in waterKhoza, M. N. L. (Mtetwa) 03 1900 (has links)
Thesis. (M. Tech. (Dept. of Biosciences, Faculty of Applied and Computer Sciences))--Vaal University of Technology, 2010 / Methods for detecting the presence of Cryptosporidium oocysts and Giardia cysts have been developed and continuous improvement is being done to improve the recovery rate of the target protozoa. Rand Water has adopted their method for isolation and detection of Cryptosporidium oocysts and Giardia cysts in water from United State Environmental Protection Agency (US-EPA) Method 1623, 1999. In 2005 changes were made by US-EPA to the Method 1623.
A study was done to improve the performance of the Rand Water Method 06 (2007) used for isolation and detection of Cryptosporidium oocysts and Giardia cysts. Three methods namely: Rand Water Method 06 (2007), US-EPA Method 1623 (2005) and Drinking Water Inspectorate standard operating procedures (2003) were compared and key different steps in the methods were identified (wrist action speed, centrifuge speed, immunomagnetic separation procedures and addition of pre-treatment steps). Different experiments were conducted to verify and evaluate the difference between two wrist action shaker speeds, three different centrifuge speeds, two slightly different immunomagnetic separation procedures and when a pre-treatment step was included in the method.
Three different types of water matrices (reagent grade water, drinking water and raw water) were used for the experiments and secondary validation. Data obtained from the experiments and secondary validation was statistically analyzed to determine whether there was a significant difference in the recovery of Cryptosporidium oocysts and Giardia cysts. Secondary validation of the Rand Water Method 06 (2007) was performed by implementing the study experiments‟ findings into the method.
The results indicated an increase in the recovery rate of Cryptosporidium oocysts and Giardia cysts when data was compared with the previous secondary validation report. The mean recovery of Cryptosporidium oocysts in reagent grade water samples increased from 31% to 55%, drinking water samples increased from 28% to 44% and raw water decreased from 42% to 29%. The mean recovery of Giardia cysts in reagent grade water samples increased from 31% to 41%, drinking water samples increased from 28% to 46% and raw water decreased from 42% to 32%.
Furthermore, even though the recovery rate of raw water decreased the use of pre-treatment buffer reduced the number of IMS performed per sample by reducing the pellet size. Enumeration of microscope slides was also easier as there was less background interference. The optimization of the Rand Water Method 06 (2007) was successful as the recovery rate of Cryptosporidium oocysts and Giardia cysts from water increased. All the changes that were verified and that increased the recovery rate were incorporated into the improved Rand Water Method 06.
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The application of water pinch analysis at AECI bioproducts.Schneider, Janos Pal Zsigmond. January 2002 (has links)
AECI Bioproducts (Bioproducts) is part of an industrial complex located at Umbogintwini, approximately 26 km south of Durban, Kwazulu-Natal. This system was selected for water pinch investigation, as it is one of the major users of freshwater on the complex and hence discharges a related quantity of wastewater, amounting to approximately 400 ML per annum. Bioproducts is a manufacturer of l-lysine, which is an animal feed additive.
Water stream flowrate and purity data, as well as operating cost information, were obtained from plant records at AECI Bioproducts. Limiting flowrate and purity conditions for the water-using operations were established from a mass balance over the entire system using the Linnhoff-March software, WaterTracker. Subject to the specified constraints and operating costs, the problem was to determine the design of the water-using subsystem. No treatment plants were included in the study, as none exist at the facility.
Three scenarios were investigated, which examined the operating variability of one of the evaporators on the site (the AS evaporator), which produces a condensate source of variable purity. The operating cost target and network design for each scenario was determined using the Linnhoff-March software, WaterPinch. Alterations from current operating practice were identified and associated savings (water-using network operating cost and freshwater flowrate) were highlighted.
A robust optimal design was identified, with a recycle, which was consistent for all scenarios investigated. The degree of reuse of the AS evaporator condensate source was determined to be dependent on the purity of the source. The limiting constraint was identified at the sea pipeline, for suspended solids (SS): a prohibitively low discharge concentration constraint was identified as posing the major obstacle for saving. The potential for saving was investigated by incrementing the SS concentration constraint and subsequently the free and saline ammonia (FSA) constraint and allowing for the broth effluent to be discharged via the sea pipeline (which was previously disallowed by an effluent exemption). Although relatively small savings were identified through process integration (from 0.61% to 1.56% of the water-using network operating cost), the analysis identified a potential saving of over 70% of the water-using network operating cost, with relaxation of the sea pipeline SS and FSA constraint. / Theses (M.Sc.)-University of Natal, Durban, 2002.
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Environnmental life cycle assessment of potable water production.Friedrich, Elena. January 2001 (has links)
This study investigates and compares the environmental burdens of two different methods for
producing potable water by using the environmental life cycle assessment (LCA). The first
method, for the production of potable water, is used by Umgeni Water at their Wiggins Waterworks
and it involves conventional processes. The second method is based on a South African membrane
technology and currently it is used in three pilot plants around the country.
The life cycle concept gives the means understand the environmental impacts associated with a
product. process or activity by considering all life-cycle stages, from cradle- to-grave. Formal
methodologies for conducting such studies have been developed and in this project the
methodological framework endorsed by the International Organisation for Standardisation (ISO)
14040 series of standards has been used.
By using this methodology and by tracing all processes involved in the production of potable water,
it was found that the main contribution towards the environmental burdens of potable water is due
to electricity generation. This conclusion is valid for both methods in vestigated. and as a result the
recommendations focus on increasing the energy efficiency of waterworks in order to increase their
overall environmental performance. / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.
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The Immune Response of Guinea Pigs as Influenced by Hypobaric Pressure and Normoxic Environment (Part I); Membrane Filter-Fluorescent-Antibody Method for Detection and Enumeration of Bacteria in Water (Part II)Reeder, Dennis James 08 1900 (has links)
In this work experimental design and tests were established to determine whether antibody production in guinea pigs injected with a bacterial antigen is Influenced by the environment of simulated high altitude with normoxic conditions. Hematological and electrophoretic studies were simultaneously run with the antibody determinations as a check on related responses of the animals.
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