Sample preparation methodologies for preconcentration of selected emerging contaminants in environmental samples
- Authors: Akawa, Mpingana Ndilimeke
- Date: 2021
- Subjects: Water resources development , Water conservation , Water quality
- Language: English
- Type: Doctoral (Thesis)
- Identifier: http://hdl.handle.net/10210/483866 , uj:43928
- Description: Abstract: The presence of pharmaceutical residues in the environment waters is a serious concern because of the possible ecotoxicological impacts related to long-term exposure of both terrestrial and aquatic ecosystem. Pharmaceuticals end up into the influent wastewater mainly through the domestic sewage system, hospital disposal of wastes, unused and expired drugs and agricultural activities. Most conventional wastewater treatment plants are not capable of efficiently removing pharmaceutical residues from wastewater before discharging effluents into the environment. This is mainly due to the presence of very low concentrations of pharmaceutical residues as well as their diverse chemical structures, modes of action and other properties. Despite the low concentrations of pharmaceutical residues in the environment, their individual toxicities as well as their combinational effects have shown to have detrimental health effects on terrestrial and aquatic organisms. However, there are no maximum discharge guidelines and standards yet, which regulates the discharges and presence of these pollutants in the environmental matrices. Therefore, it is imperative to monitor their concentrations in environmental waters to avoid health effects due to unexpected exposures of humans and other living organisms. In view of the above, the main aim of this study was to develop sample preparation methods for sample clean-up, extraction and preconcentration of pharmaceutical residues, specifically, non-steroidal antiinflammatory drugs and antiretroviral drugs in river water and wastewater matrices. This was achieved by developing four sample pre-treatment techniques which include two magnetic solid phase extraction (MSPE) methods, dispersive microsolid phase extraction (D-μSPE) and supramolecular solvent based dispersive liquid-liquid microextraction (SSDLLME). The quantification of the selected pharmaceuticals was achieved by high performance liquid chromatography equipped with diode array detector (HPLC-DAD)... , Ph.D. (Chemistry)
- Full Text:
- Authors: Akawa, Mpingana Ndilimeke
- Date: 2021
- Subjects: Water resources development , Water conservation , Water quality
- Language: English
- Type: Doctoral (Thesis)
- Identifier: http://hdl.handle.net/10210/483866 , uj:43928
- Description: Abstract: The presence of pharmaceutical residues in the environment waters is a serious concern because of the possible ecotoxicological impacts related to long-term exposure of both terrestrial and aquatic ecosystem. Pharmaceuticals end up into the influent wastewater mainly through the domestic sewage system, hospital disposal of wastes, unused and expired drugs and agricultural activities. Most conventional wastewater treatment plants are not capable of efficiently removing pharmaceutical residues from wastewater before discharging effluents into the environment. This is mainly due to the presence of very low concentrations of pharmaceutical residues as well as their diverse chemical structures, modes of action and other properties. Despite the low concentrations of pharmaceutical residues in the environment, their individual toxicities as well as their combinational effects have shown to have detrimental health effects on terrestrial and aquatic organisms. However, there are no maximum discharge guidelines and standards yet, which regulates the discharges and presence of these pollutants in the environmental matrices. Therefore, it is imperative to monitor their concentrations in environmental waters to avoid health effects due to unexpected exposures of humans and other living organisms. In view of the above, the main aim of this study was to develop sample preparation methods for sample clean-up, extraction and preconcentration of pharmaceutical residues, specifically, non-steroidal antiinflammatory drugs and antiretroviral drugs in river water and wastewater matrices. This was achieved by developing four sample pre-treatment techniques which include two magnetic solid phase extraction (MSPE) methods, dispersive microsolid phase extraction (D-μSPE) and supramolecular solvent based dispersive liquid-liquid microextraction (SSDLLME). The quantification of the selected pharmaceuticals was achieved by high performance liquid chromatography equipped with diode array detector (HPLC-DAD)... , Ph.D. (Chemistry)
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Effective management of procurement process : a potential solution for improving on the delivery of water infrastructure projects
- Authors: Mkasi, Patience Nelisiwe
- Date: 2020
- Subjects: Industrial procurement , Project management , Water resources development
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/481966 , uj:43689
- Description: M.Ing. (Engineering Management) , Abstract: Realising the effects of the dearth of water infrastructure, in quantity and quality, on the economy and social wellbeing of the citizens, the government of South Africa (SA) has continued to make significant investments in the development of suitable water infrastructure. Unfortunately, the current pace of infrastructure delivery in the water sector is not complementary to the investment, due to ineffective procurement processes that produce low performance rates of the contractors. Consequently, available quality water hardly satisfies the demands of the production industries and wellbeing of citizens; sometimes resulting in community restlessness, evident in the protests related to the lack of quality water service delivery. Therefore, it is imperative to evaluate the current procurement system that produces these low performing contractors. The research focused on the Rehabilitation of the Clan-William Dam, as a case study. Semi-structured questionnaires complemented with interviews were used as instruments for data collection. The participants were drawn from the Supply Chain Management (SCM) function unit and technical staff of the Department of Water and Sanitation, consultant and as well as from the contractor. The findings revealed that the combined effects of an ineffective project execution team, an overly centralised SCM system, the selection of incompetent contractors, ineffective bid evaluation and the complicated procurement process, were key factors responsible for the slow pace of delivery of water infrastructure in SA. Therefore, the research recommended the adoption of contractors’ pre-qualification, strengthening of the project execution team, and a decentralised SCM system, as a panacea to the improvement in water infrastructure delivery.
- Full Text:
- Authors: Mkasi, Patience Nelisiwe
- Date: 2020
- Subjects: Industrial procurement , Project management , Water resources development
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/481966 , uj:43689
- Description: M.Ing. (Engineering Management) , Abstract: Realising the effects of the dearth of water infrastructure, in quantity and quality, on the economy and social wellbeing of the citizens, the government of South Africa (SA) has continued to make significant investments in the development of suitable water infrastructure. Unfortunately, the current pace of infrastructure delivery in the water sector is not complementary to the investment, due to ineffective procurement processes that produce low performance rates of the contractors. Consequently, available quality water hardly satisfies the demands of the production industries and wellbeing of citizens; sometimes resulting in community restlessness, evident in the protests related to the lack of quality water service delivery. Therefore, it is imperative to evaluate the current procurement system that produces these low performing contractors. The research focused on the Rehabilitation of the Clan-William Dam, as a case study. Semi-structured questionnaires complemented with interviews were used as instruments for data collection. The participants were drawn from the Supply Chain Management (SCM) function unit and technical staff of the Department of Water and Sanitation, consultant and as well as from the contractor. The findings revealed that the combined effects of an ineffective project execution team, an overly centralised SCM system, the selection of incompetent contractors, ineffective bid evaluation and the complicated procurement process, were key factors responsible for the slow pace of delivery of water infrastructure in SA. Therefore, the research recommended the adoption of contractors’ pre-qualification, strengthening of the project execution team, and a decentralised SCM system, as a panacea to the improvement in water infrastructure delivery.
- Full Text:
Audit tools to assess, quantify, monitor and report on impacts on water resources at a catchment unit level
- Authors: Henman-Weir, Felicity
- Date: 2017
- Subjects: Water resources development , Water resources development - Law and legislation , Sustainable development
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/285071 , uj:30813
- Description: M.Sc. (Aquatic Health) , Abstract: The purpose of this study was to develop a suite of checklists that could be used to audit rural land-users within a catchment to determine their impacts on the water resources and in doing so, also audit their legal compliance. The need for this was in response to the ongoing deterioration of South Africa’s water resources. The legislation pertaining to water use and water protection and certain best practice guidelines were used as the base of these checklists. The key legislation was the National Water Act (36 of 1998), National Environmental Management Act (107 of 1998), and the Conservation of Agricultural Resources Act (43 of 1983) and the regulations emerging from these Acts pertaining to water use and protection. Checklists were drawn up for the main land-uses: Agriculture, Commercial Plantation Forestry, Aquaculture and General Land-Use (e.g. recreation and tourism, rural settlements). A set of eight (8) checklists were collated to cover all of the impacts likely to occur in a catchment, namely: Vegetation removal and clearing; Pollution; Alien invasive plants; Alien fauna; Mining (small scale); Water abstraction; Storing water (reservoirs and weirs), and Watercourse crossings. These checklists were field tested by carrying out an audit of an aquaculture facility (Trova Trout) and commercial plantation forestry (Komatiland Forests) within the Upper Sabie River Catchment, above the town of Sabie. These two land uses scored 46% and 49 % respectively through the audit system, and numerous legal non-conformances were noted. Audit report templates were also generated in order to capture the audit results for comparison over time. Results for Trova Trout were presented in such a formal audit report. Abstraction of water from the Sabie River without metering, development within riparian zones and the impact of hundreds of watercourse crossings in the catchment emerged as some of the issues as a result of the audit. It was concluded that the tools developed were suitable for auditing land-users within a catchment, and served to expose the impacts on water resources. Some case studies were investigated and it is clear that water related offences are not yet fully acknowledged as serious crimes by South Africans. As a result, recommendations included the establishment of special Environmental Courts, building the capacity of the Environmental Management Inspectorate and implementing pro-active auditing programmes within catchments.
- Full Text:
- Authors: Henman-Weir, Felicity
- Date: 2017
- Subjects: Water resources development , Water resources development - Law and legislation , Sustainable development
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/285071 , uj:30813
- Description: M.Sc. (Aquatic Health) , Abstract: The purpose of this study was to develop a suite of checklists that could be used to audit rural land-users within a catchment to determine their impacts on the water resources and in doing so, also audit their legal compliance. The need for this was in response to the ongoing deterioration of South Africa’s water resources. The legislation pertaining to water use and water protection and certain best practice guidelines were used as the base of these checklists. The key legislation was the National Water Act (36 of 1998), National Environmental Management Act (107 of 1998), and the Conservation of Agricultural Resources Act (43 of 1983) and the regulations emerging from these Acts pertaining to water use and protection. Checklists were drawn up for the main land-uses: Agriculture, Commercial Plantation Forestry, Aquaculture and General Land-Use (e.g. recreation and tourism, rural settlements). A set of eight (8) checklists were collated to cover all of the impacts likely to occur in a catchment, namely: Vegetation removal and clearing; Pollution; Alien invasive plants; Alien fauna; Mining (small scale); Water abstraction; Storing water (reservoirs and weirs), and Watercourse crossings. These checklists were field tested by carrying out an audit of an aquaculture facility (Trova Trout) and commercial plantation forestry (Komatiland Forests) within the Upper Sabie River Catchment, above the town of Sabie. These two land uses scored 46% and 49 % respectively through the audit system, and numerous legal non-conformances were noted. Audit report templates were also generated in order to capture the audit results for comparison over time. Results for Trova Trout were presented in such a formal audit report. Abstraction of water from the Sabie River without metering, development within riparian zones and the impact of hundreds of watercourse crossings in the catchment emerged as some of the issues as a result of the audit. It was concluded that the tools developed were suitable for auditing land-users within a catchment, and served to expose the impacts on water resources. Some case studies were investigated and it is clear that water related offences are not yet fully acknowledged as serious crimes by South Africans. As a result, recommendations included the establishment of special Environmental Courts, building the capacity of the Environmental Management Inspectorate and implementing pro-active auditing programmes within catchments.
- Full Text:
An investigation into the alleviation and management of the water supply shortage in Gauteng
- Ngoune, Severin Merimee Delaire
- Authors: Ngoune, Severin Merimee Delaire
- Date: 2015
- Subjects: Water resources development , Water-supply - South Africa - Gauteng - Management , Water consumption - South Africa - Gauteng - Management
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/242424 , uj:25004
- Description: Abstract: South Africa is a semi-arid country faced with an enormous water supply management challenge, and is therefore classified as a water stressed country. However, in addition to this matter, the management of the available water resources, the facilities, the infrastructure as well as the forecasting have failed. The major difficulties of services providers and delivery is related to the identification of how to manage their responsibility to supply continuous, acceptable, reliable and safe water to consumers. In an effort to address the current challenge, a methodical management system is the key to tackle issues and continuously improve water supply services. This study investigated approaches to manage and alleviate the water supply shortage and to determine the gaps which contribute to the water shortage by considering the application of Lean Six Sigma tools analysis using the localities of Sebokeng/Evaton as case studies. A quantitative research methodology using a closed ended questionnaire was adopted to collect and analyse data. The findings of the study revealed there are many issues related to the water management challenge. This is due to the fact that water supply schemes are in a poor condition because of a lack of proper operation, maintenance, lack of infrastructure and facilities, whilst the available water resources are limited. The core of the water supply shortage, which has resulted in the failure of the management system is directly related to the lack of effective or appropriate management techniques to identify and improve significantly the water supply shortage. The management of water schemes, in particular the operation and maintenance, is a principal problem in ensuring assurance of the water supply. The results of a Pareto analysis also shows 80% of the defects and the order in which the problems must be resolved. It is therefore recommended that to provide an adequate and reliable supply of safe water to the consumer, management operation and maintenance activities need to be continuously fulfilled in order to achieve better performance in all processes within the provider services. It appears that a methodical approach to management is required to resolve these issues related to failure of management, or an inappropriate approach to water management techniques. Use of sea water could be a reliable long term solution to the problem of water scarcity. , M.Tech. (Operations Management)
- Full Text:
- Authors: Ngoune, Severin Merimee Delaire
- Date: 2015
- Subjects: Water resources development , Water-supply - South Africa - Gauteng - Management , Water consumption - South Africa - Gauteng - Management
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/242424 , uj:25004
- Description: Abstract: South Africa is a semi-arid country faced with an enormous water supply management challenge, and is therefore classified as a water stressed country. However, in addition to this matter, the management of the available water resources, the facilities, the infrastructure as well as the forecasting have failed. The major difficulties of services providers and delivery is related to the identification of how to manage their responsibility to supply continuous, acceptable, reliable and safe water to consumers. In an effort to address the current challenge, a methodical management system is the key to tackle issues and continuously improve water supply services. This study investigated approaches to manage and alleviate the water supply shortage and to determine the gaps which contribute to the water shortage by considering the application of Lean Six Sigma tools analysis using the localities of Sebokeng/Evaton as case studies. A quantitative research methodology using a closed ended questionnaire was adopted to collect and analyse data. The findings of the study revealed there are many issues related to the water management challenge. This is due to the fact that water supply schemes are in a poor condition because of a lack of proper operation, maintenance, lack of infrastructure and facilities, whilst the available water resources are limited. The core of the water supply shortage, which has resulted in the failure of the management system is directly related to the lack of effective or appropriate management techniques to identify and improve significantly the water supply shortage. The management of water schemes, in particular the operation and maintenance, is a principal problem in ensuring assurance of the water supply. The results of a Pareto analysis also shows 80% of the defects and the order in which the problems must be resolved. It is therefore recommended that to provide an adequate and reliable supply of safe water to the consumer, management operation and maintenance activities need to be continuously fulfilled in order to achieve better performance in all processes within the provider services. It appears that a methodical approach to management is required to resolve these issues related to failure of management, or an inappropriate approach to water management techniques. Use of sea water could be a reliable long term solution to the problem of water scarcity. , M.Tech. (Operations Management)
- Full Text:
Effects of dams on river water quality: a case study of Lesotho Highlands Water Project
- Authors: Nyakale, James Mogorosi
- Date: 2012-07-19
- Subjects: Lesotho Highlands Water Project , Water resources development , Water quality biological assessment
- Type: Mini-Dissertation
- Identifier: uj:8831 , http://hdl.handle.net/10210/5244
- Description: M.Sc. , The Senqu-Orange basin is the principal carrier of the mean annual runoff for the larger portion of South Africa, encompassing also Lesotho. The transformation of this river regime by inter-basin transfer from south-westerly flowing rivers to the northerly flowing Senqu-Orange system of water as a resource may have adverse impacts on freshwater quality of ecosystems. This report presents a case study of the Lesotho Highlands Water Project (Phase 1), investigating alterations of physical and chemical water quality caused by the three types of large infrastructure: a dam (Mohale Dam); a dam and weir (Katse Dam and Matsoku Weir); and a delivery tunnel (from ’Muela Dam to the Ash River Outfall). The aim of the study was to determine significant differences, if any, of selected water quality variables in water released or transported from the infrastructure, using water from an undisturbed sampling site located on the Senqu River as a reference. Analyses are carried out of longterm trends and variations of the following selected water quality variables: pH, conductivity, total nitrogen, magnesium and sodium. Sampling station sites, operated by South Africa Department of Water Affairs and Forestry from 1990 to 2003, are located at the Malibamatso, Senqunyane, Matsoku, Senqu and Ash rivers. Time series graphs were used for analysing long-term trends. ANOVA or the H-test and Scheffé multiple comparison statistical test methods were used to determine significant differences. Total suspended solids (TSS) and turbidity measurements, together with discharge rates, were made available from a study by the Lesotho Highlands Development Authority from January 1998 to September 1999, for two sites downstream of Matsoku Weir and Mohale Dam. Short-term temporal water quality effects due to dam discharges were assessed. pH values are uniform, and comply to target water quality range (TWQR) guidelines of the Department of Water Affairs and Forestry. There are no long-term trends for total nitrogen, conductivity, magnesium and sodium. There are records of intermittent episodes of total nitrogen exceeding TWQR, caused possibly by anoxic conditions of the artificial impoundments associated with the three types of large infrastructure. Total suspended solids were affected by discharge rates - concentrations increased with increasing flow ii discharge of surface water. Turbidity values increased in association with enhanced TSS concentrations, although this is not a causal relationship. From statistical evaluations, significant variations in pH were observed between each test site (dam, dam and weir, and delivery tunnel) and the reference site. The group means in pH at each test site were lower than the reference site. Scheffé test results indicted significant difference in total nitrogen between the dam, the delivery tunnel and the reference site, but not for the dam and weir in relation to the reference site. Similarly, mean concentrations of total nitrogen were lowest at delivery tunnel and the dam. Although, significant differences were observed for conductivity, sodium and magnesium between the dam and weir, and the reference location, such variations are attributable to the Senqu River valley and not the infrastructure of the transfer scheme. Thus, results from the assessment of significant differences in conductivity, sodium and magnesium at the dam and delivery tunnel were unreliable and discarded.
- Full Text:
- Authors: Nyakale, James Mogorosi
- Date: 2012-07-19
- Subjects: Lesotho Highlands Water Project , Water resources development , Water quality biological assessment
- Type: Mini-Dissertation
- Identifier: uj:8831 , http://hdl.handle.net/10210/5244
- Description: M.Sc. , The Senqu-Orange basin is the principal carrier of the mean annual runoff for the larger portion of South Africa, encompassing also Lesotho. The transformation of this river regime by inter-basin transfer from south-westerly flowing rivers to the northerly flowing Senqu-Orange system of water as a resource may have adverse impacts on freshwater quality of ecosystems. This report presents a case study of the Lesotho Highlands Water Project (Phase 1), investigating alterations of physical and chemical water quality caused by the three types of large infrastructure: a dam (Mohale Dam); a dam and weir (Katse Dam and Matsoku Weir); and a delivery tunnel (from ’Muela Dam to the Ash River Outfall). The aim of the study was to determine significant differences, if any, of selected water quality variables in water released or transported from the infrastructure, using water from an undisturbed sampling site located on the Senqu River as a reference. Analyses are carried out of longterm trends and variations of the following selected water quality variables: pH, conductivity, total nitrogen, magnesium and sodium. Sampling station sites, operated by South Africa Department of Water Affairs and Forestry from 1990 to 2003, are located at the Malibamatso, Senqunyane, Matsoku, Senqu and Ash rivers. Time series graphs were used for analysing long-term trends. ANOVA or the H-test and Scheffé multiple comparison statistical test methods were used to determine significant differences. Total suspended solids (TSS) and turbidity measurements, together with discharge rates, were made available from a study by the Lesotho Highlands Development Authority from January 1998 to September 1999, for two sites downstream of Matsoku Weir and Mohale Dam. Short-term temporal water quality effects due to dam discharges were assessed. pH values are uniform, and comply to target water quality range (TWQR) guidelines of the Department of Water Affairs and Forestry. There are no long-term trends for total nitrogen, conductivity, magnesium and sodium. There are records of intermittent episodes of total nitrogen exceeding TWQR, caused possibly by anoxic conditions of the artificial impoundments associated with the three types of large infrastructure. Total suspended solids were affected by discharge rates - concentrations increased with increasing flow ii discharge of surface water. Turbidity values increased in association with enhanced TSS concentrations, although this is not a causal relationship. From statistical evaluations, significant variations in pH were observed between each test site (dam, dam and weir, and delivery tunnel) and the reference site. The group means in pH at each test site were lower than the reference site. Scheffé test results indicted significant difference in total nitrogen between the dam, the delivery tunnel and the reference site, but not for the dam and weir in relation to the reference site. Similarly, mean concentrations of total nitrogen were lowest at delivery tunnel and the dam. Although, significant differences were observed for conductivity, sodium and magnesium between the dam and weir, and the reference location, such variations are attributable to the Senqu River valley and not the infrastructure of the transfer scheme. Thus, results from the assessment of significant differences in conductivity, sodium and magnesium at the dam and delivery tunnel were unreliable and discarded.
- Full Text:
Development of a conservation program on Pseudobarbus quathlambae in the catchment area of phase 1B of the Lesotho Highlands Water Project
- Authors: Rall, Johannes Lambertus
- Date: 2009-09-21T09:33:48Z
- Subjects: Minnows , Cyprinidae , Rare fishes , Stream ecology , Water resources development , Lesotho
- Type: Thesis
- Identifier: http://ujcontent.uj.ac.za8080/10210/370615 , uj:8631 , http://hdl.handle.net/10210/2971
- Description: D.Phil.
- Full Text: false
- Authors: Rall, Johannes Lambertus
- Date: 2009-09-21T09:33:48Z
- Subjects: Minnows , Cyprinidae , Rare fishes , Stream ecology , Water resources development , Lesotho
- Type: Thesis
- Identifier: http://ujcontent.uj.ac.za8080/10210/370615 , uj:8631 , http://hdl.handle.net/10210/2971
- Description: D.Phil.
- Full Text: false
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