Conference Abstracts

All Abstracts were presented at the Groundwater Conferences

Displaying 201 - 250 of 795 results

Title	Presenter Name Sort descending	Presenter Surname	Area	Conference year	Keywords
Using geophysics to detect water-hosting fractures in the Vredefort Dome: A training opportunity	Elvis	Tamilo	Gauteng	2021	Poster, Geophysics
Abstract Enslin,S; Webb, SJ The Vredefort Dome 120 km southwest of Johannesburg is a meteorite impact crater that formed at approximately 2 Ga. The region hosts farmland, and the town of Parys is situated in the northwestern part of the dome. The dome is the location of the annual Wits University/AfricaArray Geophysical Field School. The aim of the field school is to teach geoscience students several geophysical techniques while conducting scientific research in the area. A geophysical survey during the 2019 field school over an open field just outside of Parys revealed a buried fracture that hosts ground water. A 150 m long magnetic profile over the fractures shows a magnetic low (approximately 500 nT) that correlates with a low resistivity region on the inverted electrical resistivity data (dipole-dipole method). Euler deconvolution depth estimates and magnetic modelling estimate an overburden thickness of around 10 m and a similar fracture thickness. The magnetic low of the fracture is due to weathering and removal of any magnetic material in the granites in the region. Two existing boreholes that lie 618m due south and at a 10 m lower elevation have water levels of around 6.4 m. Both boreholes lie near a riverbed and vegetation, and appear to lie along an extension to the fracture. This fractures detected using geophysical methods seems to form part of a larger fracture system within the Vredefort Dome, that is linked to the formation of the dome. These fractures provide a vital source of water for the local farming community.
AI_GEO software platform for regional groundwater potential mapping	Emannuel	Sakala	Free State	2021	Mapping methodologies, AI, algorithms, Drought, exploitation potential
Abstract Delineation of groundwater resources of a given area is importance for management of groundwater resources. This is often done manually by combining various geo-scientific datasets in Geographic Information System (GIS) environment, which is time consuming and is prone to subjective bias and also suffers from other human induced uncertainties and difficult to cope with increasing volumes of data. The explosive growth of data leading to ‘rich data, but poor knowledge’ dilemma yet we have challenges to be solved. Artificial Intelligence (AI) has been successfully used in fields such as robotics, process automation in engineering, industry, medical and domestic households. Artificial Intelligence tool have the able to bridge this gap by augmenting the human capabilities in understand science far better than before. Incorporating AI into groundwater potential mapping greatly improves computation speed, reduces the subjectivity nature of manual mapping and lessens human induced uncertainties. The software platform includes artificial intelligence algorithms such as artificial neural networks, support vector machines, random forest, index-overlay and fuzzy logic. The software platform is semi-automatic to allow the user to control some of the processes yet automating the other processes. The possible inputs to the AI for training includes; aquifer types, topographic slope, lineament and drainage density, land-use / land-cover (LULC), distance to lineaments, distance to streams and soil clay content. Yield values of selected boreholes are used as training outputs. The software was tested using data gathered for the area surrounding Maluti-a-Phong in the Free State Province of South Africa. The area was chosen because of recent drought which has hit the country and local municipalities are searching for groundwater resources for building wellfields to supply local communities with fresh water. The groundwater potential map of the area was validated using borehole yield values of boreholes which were not used for modelling. Good correlation values as high as 0.85 was obtained between model values and borehole yield. The final groundwater potential map was divided into four zones; very good, good, poor and very poor. Based on this study, it is concluded that the high groundwater potential zones can be target areas for further hydrogeological studies. The usage of the software proved to be efficient in minimising the time, labour and money needed to map large areas. The results of which can be used by local authorities and water policy makers as a preliminary reference to narrowed down zones to which local scale groundwater exploration can be done. AI should be viewed as augmented intelligence as it aid the decision-making process rather than replacing it. Data-driven approaches should also be knowledge-guided for efficient results.
Using passive sampling to identify trends in aquatic pesticide pollution in the Western Cape, South Africa	Emma	Davies	Western Cape, South Africa	2023	Imidacloprid, passive water sampling, pesticide, South Africa, surface water, Sustainable Development Goal
Abstract South Africa is the leading user of pesticides in Sub-Saharan Africa, but data on pesticide occurrence in (ground)water is limited. Consequently, there is a need to improve knowledge on transport pathways that cause pesticides to enter the aquatic environment. This research monitored pesticide concentrations in three agricultural catchments in the Western Cape, South Africa, including Grabouw (pome fruit), Hex River Valley (table grapes), and Piketberg (wheat). Passive samplers were deployed in rivers from March 2022- March 2023, adding to a 2017-2019 dataset of analytical and pesticide application data. Field and laboratory methods were developed at Stellenbosch University to measure pesticides using Liquid Chromatography-Mass Spectrometry. For quality control, duplicate samples were analyzed at Eawag, Switzerland. 30 compounds were detected, yet two/three comprise most of the total mass, including an analyte not considered in earlier investigations (dimethomorph). Rainfall-flow relationships and agricultural application could only partially explain detection levels, suggesting that other factors, including non-agricultural application or groundwater input, might influence detections. Two compounds exceeded European Environmental Quality Standards (chlorpyrifos and imidacloprid). Imidacloprid is particularly concerning because it exceeded consistently despite few recorded applications. 2017-2022 imidacloprid data indicates a decreasing concentration trend in Hex River Valley and increasing trends in Piketberg and Grabouw. Consistently high detections during wet and dry periods suggest groundwater input. However, such pesticide transport pathways are poorly understood due to a lack of local evidence. Local authorities must establish a long-term monitoring program to understand better the risk pesticides pose to the aquatic environment and human health.
Automation Of Interpretation Of Geoelectrical Resistivity Using Artificial Intelligence	Emmanuel	Sakala		2019	Resistivity, AI
Abstract Artificial Intelligence (AI) has been used in a variety of problems in the fields of science and engineering in particular automation of many processes due to their self-learning capabilities as well as their noise-immunity. In this paper, we describe a study of the applicability of one of the popular branch of AI (Artificial Neural Network (ANN)) as an alternative approach to automate modelling of one-dimensional geoelectrical resistivity sounding data. The methodology involves two ANNs; first one for curve type identification and the other one for model parameter estimation. A three-layer feedforward neural network that was trained from geoelectrical resistivity data taken at boreholes with geology logs was used to predict earth models from measured data without the need to guess the initial model parameters or use synthetic data as is done with most conventional inversion approaches. The motivation for using the ANN for geophysical inversion is that they are adaptive systems that perform a non-linear mapping between two sets of data from a given domain. For network training, we use the back-propagation algorithm. An example using data from southern Malawi shows that the ANN results outperforms the conventional approaches as the results after adequate training, produce reasonably accurate earth models which are in agreement with borehole log data.
Investigation Of Possible Contaminant Plumes Emanating From Residual Mine Deposits In The Mpumalanga Province Of South Africa, Results From Geophysical Surveys	Emmanuel	Sakala	Mpumalanga	2013	contamination, plumes, geophysical methods
Abstract Acid-mine drainage (AMD) has received considerable media coverage in South Africa as of late. This have caused a considerable increase in researches, most of them with emphasis on decanting of contaminated water from the old gold mines in Witwatersrand basins and fewer on mine residue contamination from coal and gold mines in the Mpumalanga Province. The paper outlines results of ground geophysical surveys that were carried out along the perimeter of two mine residual deposits (dumps) in the Barberton Greenstone Belt, Mpumalanga Province. The aim of the study was to generate a 3D geoelectric model of the subsurface showing possible acid-mine drainage contaminant pathways. Two geophysical methods, namely Frequency Domain Electromagnetic Profiling (FDEM) and Electrical Resistivity Tomography (ERT) were applied in order to investigate the variation of electrical conductivity in the subsurface. The ERT method was done over frequency domain electromagnetics anomalies. FDEM electrical conductivity values ranging between 40 mS/m to 60 mS/m were considered as anomalous in that geological terrain. These areas were then surveyed by the ERT method to check the depth extent of these FDEM anomalies. On the resistivity section, between station 40 m and 80 m of Dump 1 – ERT1, a discontinuity in the bedrock was identified. The area could act as a pathway for contaminants to flow from the dump to groundwater. The FDEM survey identified an area with high conductivity values to the north of Dump 1. The ERT results also showed a shallow plume at 30 m depth which is consistent on two parallel sections on Dump 1. The area could be a possible AMD pathway of a mine dump residue to a Komati tributary on the north. The bedrock is generally characterised by high resistivity values; a break in the bedrock exists on this high resistivity zone on ERT 6. This break could be a fault zone which can act as possible pathway of (AMD) from a mine dump residue to a shallow aquifer. Potential contaminant recharge pathways were delineated using geophysical, electrical and electromagnetic methods. Potential groundwater recharge pathways and sub-vertical low resistivity zones with values <100Ohm.m were delineated using the ERT method. Investigation of contaminant plume migration is recommended over the anomalies that were generated from geophysics data in the Barberton areas. New technologies (artificial neural networks (ANN), fuzzy logic, etc.) combined with laboratory studies is recommended for development of a software platform that accepts 3D geoelectric data (present study), constrained with geology, geochemistry (soil and water), hydrology and hydrogeology data.
Supervised committee artificial neutral network in groundwater exploration in granitic and metamorphic terrains of South Africa	Emmanuel	Sakala	Northern Cape	2015
Abstract POSTER The areas studied in this paper are situated in semi-dry regions of Limpopo and Northern Cape Provinces of South Africa. Groundwater is the only dependable source of water for many local users and farming communities. The growing population is putting immense pressure in the current water resources, hence a need to find new groundwater resources. The areas are most dominated by fractured rock aquifers which accounts to over 90% of South African aquifers. Finding sustainable sources of groundwater in these regions is often a challenge due the complex nature of the fracturing network system of fractured aquifers. This study uses a supervised committee learning with artificial neutral network (SCLANN) model to improve the regional groundwater exploration in granitic basement terrains and valley controlled aquifers in metamorphic terrains of South Africa. The data used in the study was obtained from the national groundwater archive and interpretation of high resolution aeromagnetic data, ground surveys and remote sensing datasets. The artificial neural network (ANN), Fuzzy (F) and Neuro-fuzzy (NF) unsupervised models whose input were groundwater controlling parameters like regolith thickness, lithology, relief, faults, lineament density, lengths of lineaments was used. The results from the ANN, F and NF models were used as inputs to a nonlinear supervised SCLANN framework with the borehole yield as the training and validation outputs. Borehole yield was used as it is one of the measurable parameter that directly related to productivity of groundwater resources. The use of the unsupervised models improved the results significantly as the SCLANN model results as a combined advantage of the individual models to achieve the optimal high performance. The results show that the three models used to build a SCLANN model was able to improve the identification of potential groundwater targets at regional scales. This approach can be incorporated in regional groundwater exploration programs to improving drilling success rate on granitic basement and metamorphic terrains in South Africa. The results show that the SCLANN outperforms individual unsupervised models. However the SCLANN results for granitic basement terrains were far much better than the metamorphic terrains probably showing the limitation of the approach in metamorphic terrains.
Investigation of possible contaminant plumes emanating from residual mine deposits in the Limpopo Province of South Africa	Emmanuel	Chirenje	Mpumalanga	2015
Abstract Acid mine drainage (AMD) has lately received considerable media coverage in South Africa. This has caused considerable increase in researchers most of them with emphasis on decantation of contaminated water from the old gold mines in Witwatersrand basins and fewer on mine residue contamination from Coal and Gold mines in Mpumalanga and Limpopo provinces. The paper outlines results of ground geophysical surveys that were carried out along the perimeter of two mine dumps in the Barberton Greenstone belt in the Mpumalanga Province, South Africa. The aim of the study was to generate a 3D geo-electric model of the subsurface showing possible acid mine drainage contaminant pathways. Two geophysical methods namely Frequency Domain Electromagnetic profiling (FDEM) and electrical resistivity tomography (ERT) were applied in order to investigate the variation of electrical conductivity in the subsurface. ERT method was done over frequency domain electromagnetics anomalies to further investigate depth extent of the anomalies. {List only- not presented} On the resistivity section ERT1 of Dump 1, a discontinuity in the bedrock was identified. The FDEM survey identified an area with high conductivity values to the north of Dump 1. The ERT results show a shallow plume at 20m depth, which is consistent on two parallel sections on Dump 1. The area could be a possible pathway of mine dump residue (AMD) to a stream in the north. The bedrock is generally characterized by high resistivity values; a break in the bedrock exists on this high resistivity zone on ERT 6. The identified breaks in the bedrock in terms of resistivity could be a fault zone which can act as possible pathway of mine dump residue (AMD) to a shallow aquifer. Potential contaminant recharge pathways were delineated using geophysical electrical and electromagnetic methods. Potential groundwater recharge pathways and sub-vertical low resistivity zones with values <100 Ohm.m were delineated using the ERT method. Investigation of contaminant plume migration is recommended over the anomalies that were generated from geophysics data in the Barberton areas. KEYWORDS Acid mine drainage, Frequency Domain Electromagnetic profiling and electrical resistivity tomography
Petroleum Hydrocarbons Contamination in Soil and Groundwater: Case Study on the Coastal Tank Farm, Southern Africa	Erasmus	Chauke	Indian Ocean coastal zone	2015	tank farms, soil contamination
Abstract In this study, petroleum hydrocarbon contamination assessment was conducted at a cluster of petroleum products storage and handling facilities located on the Southern African Indian ocean coastal zone. The Port Development Company identified the need for the assessment of the soil and groundwater pollution status at the tank farms in order to develop a remediation and management plan to address hydrocarbon related soil and groundwater contamination. Previous work conducted at the site before consisted out of the drilling and sampling of a limited number of boreholes. The current investigation was triggered by the presence of free phase product in the coal grading tippler pit located ~350 m down gradient and south-east and east of the tank farms, rendering the operation thereof unsafe. The assessment intended identifying the source of product, distribution and mobility, the extent of the contamination, and the human health risks associated with the contamination. To achieve these, the investigation comprised site walkover and interviews, drilling of 76 hand auger and 101 direct push holes to facilitate vertical soil profile VOC screening and sampling (soil and groundwater) as well as granulomeric analysis to understand grain size distribution within the soil profile. The highest concentrations were associated with the coarse sand layers with the highest permeability. Free phase hydrocarbons product was found in holes adjacent to the pipeline responsible for the distribution of the product form the jetty to the different tanks farms. Of the 57 soil samples, 21 had high values of GRO and DRO, with 22 below Detection Limit and 14 can be described having traces of hydrocarbon. Both TAME and MTBE were detected in most of the water samples taken, including from wells located far down gradient. The groundwater sink, adjacent to the pipeline running from west to east, resulted in the limited lateral spread of MBTE in this area, with limited movement towards the sea. The depth of the soil contamination varies over the sites. Based on the site assessment results it was concluded that most of the groundwater contamination, which is a mixture of different product types, is associated with the pipeline responsible for transporting product from the jetty to the different petroleum companies. {List only- not presented}
Characterisation of submarine groundwater discharge into False Bay (Western Cape)	Eric	Petermann	Western Cape	2015
Abstract In this paper we present results of a field study that focused on the characterisation of submarine groundwater discharge (SGD) into False Bay (Western Cape) with emphasis on its localisation. SGD is defined here as any flow of water from the seabed to the ocean. Thus, it includes (1) advective flow of fresh terrestrial groundwater as well as (2) seawater that is re-circulated across the ocean / sediment interface. Groundwater discharge into the coastal sea is of general interest for two reasons: (i) it is a potential pathway of contaminant and nutrient flux into the ocean, and (ii) it may result in the "loss" of significant volumes of freshwater. In our investigation we applied environmental aquatic tracers, namely radionuclides of radon (222-Rn) and radium (223-Ra, 224-Ra), as well as physical water parameters (salinity and temperature). The concentrations of radon and radium can be used as tracers for groundwater discharge since radon and radium are highly enriched in groundwater relative to seawater. We conducted discrete point measurements of seawater and of terrestrial groundwater as well as continuous radon time-series measurements of near-coastal seawater. A large-scale survey was performed along the entire shoreline of False Bay and revealed distinct positive anomalies of radon in the area of Strand/Gordons Bay and a rather diffuse anomaly along the Cape Flats, which is indicating possible groundwater discharge in these areas. The location of these anomalies remained constant to a large extent throughout several surveys that were performed during different seasons, although these anomalies varied with regard to their magnitude and clearness. Further detailed studies were undertaken in the area of Strand/Gordons Bay including radon time-series measurements in the coastal sea at a fixed location in order to estimate the quantity of SGD and its variability on a tidal time scale. The results indicate that groundwater discharge rates are significantly elevated during low tide. Furthermore, the distribution of radium isotopes (224-Ra/223-Ra ratios) in the Strand/Gordons Bay area indicate a "groundwater" residence time of less than 10 days within a distance of 5 km from the shore. In summary, we found spatially considerable constant SGD locations during different field campaigns. Additionally, we gained a rough understanding of the SGD dynamics on a tidal time scale, its magnitude and groundwater residence time within the inner bay after discharge. These results can be beneficial to trace back contamination in near-coastal waters or to find potential locations for groundwater abstraction.
Municipal Management And Geohydrological Aspects Of Importance In Municipal Potable Water Supply: The Case Of Lindley	Eric J	Nealer	Lindley	2013	Municipalities, Governance, potable water supply, skills development
Abstract When the South African Government in 1998 re-demarcated its 283 municipalities in such a manner that they now completely cover the country in a “wall-to-wall” manner (Section 21), their main focus was on facilitation of effective and sustainable developmental municipal management; in other words, the improvement of basic municipal services such as formalised municipal basic services (for example, safe potable water, effective refuse removal and environmental health) to all the residents of the new geographical areas consisting of millions of citizens who previously might have been neglected. Unfortunately, it seems like topographical, physical and environmental characteristics of all the resulting municipal areas have been negated in this important demarcation process. Fuggle and Rabie (2005:315) are of the opinion that this can lead to ineffective, inefficient and non- economical municipal management of basic services. By means of a literature review as well as the use and study of geographical tools such as maps, ortho-photos and information data bases, and field visits, the bare essential geographical and geo- hydrological aspects of importance for the municipal service providers and managers in the Lindley area have been identified. From this research and various other obvious reasons (for example, deteriorating physical environment due to pollution, sub-standard storm water and sewage management, and migration [informal settlements] and increasing sophisticated needs of municipal residents), the presenters of this paper want to state that the quest for improved cooperative governance in the developing South Africa, and especially in the case of the Lindley town’s geographical area of responsibility, must be facilitated according to the DWA identified surface water catchment regions. In conclusion, the presenters will recommend adherence to the following requirements as essential: An environmental, holistical and integrated management (IWRM) approach by all the involved and committed role-players, researchers and stakeholders must be adopted in the whole Vals River catchment. Effective co-operative governance must be facilitated and maintained. Basic hydrological, geo-hydrological and engineering geology knowledge and skills must be identified, obtained, modified into layman language and incorporated in the afore- mentioned approaches.
Transport and Fate of chemical and microbial tracers at UWC campus site, Cape Flats aquifer of South Africa	Erin	Haricombe	Western Cape	2015	biological tracers, chemical tracers
Abstract Different biological and chemical transport results are evaluated in this study. Ecoli and PDR1 were selected as the biological tracers with salt and rhodamine as chemical tracers. The transport experiments were evaluated through the primary aquifer material found at the University of the Western Cape research site. A series of controlled experiments under laboratory and field conditions was conducted. Each provides a different kind of data and information. The results from laboratory studies could be used to better design the field studies. In both cases, the data collected was to provide information on fate and transport of microbes in groundwater. The field design phase of the experiment was an up-scaling of the laboratory phase of this project. The amount injected into the aquifer was increased in proportion to the size of the research site. Tracer tests using chemical and microbial tracers were carried out simultaneously. Results of laboratory tests show a 5 times slower transport of microbes, compared to salts.. The salts at field scale show a breakthrough occurring after 2 days whereas the microbes never managed to breakthrough with the experiment stopped after 45 days. A new borehole was drilled closer to reduce distance/ travel time, but this had no effect on field results for the microbes. {List only- not presented}
Contaminated soil and groundwater: Vacuum Enhanced Recovery as an alternative method	Ernest	Rambau	South Africa	2015	Vacuum Enhanced Recovery, hybrocarcon contamination
Abstract Vacuum Enhanced Recovery (VER) has widely been applied in many hydrocarbon contaminated site to recover liquid hydrocarbon from the subsurface Hydrocarbon contamination to groundwater and soil is usually as results of leak or release. Different technologies and method exist to treat contaminated groundwater and soil through hydrocarbon. This paper focuses on the efficiency of VER as alternative method to the site where over 6 000 litres of petrol leaked to the subsurface over a period of time. The application of VER involves creating a capture zone in a particular monitoring well by increasing the hydraulic gradient towards that particular well or set of wells affected by hydrocarbon.
Baseline concentrations of radionuclides in groundwater of the Namibian Uranium Province, Namib Desert, western Namibia	Ester	Gustavo	Western Namibia		Namib Desert, baseline, Groundwater, radionuclides, uranium province
Abstract The Namibian uranium province, located in the Namib Desert, derives its name from the local presence of almost ten uranium tenements. The mines conduct monitoring of natural radionuclide concentrations of Ra226, Ra228, Pb210, U234, U238, Th232 and Po210 in local aquifers. This data is useful in mine rehabilitation and developing closure criteria, as only radiation doses additional to natural doses are usually considered ‘controllable’ for radiation protection purposes. An accredited laboratory analyzed the baseline data collected through quarterly groundwater sampling with submersible pumps. The uranium deposits are hosted in Damara age granites or as secondary mineralization in Tertiary calcareous paleochannels. The analysis of the long-term baseline data provides the background radionuclide concentrations of three aquifer types in the province, i.e., the Quaternary saturated alluvium of the Khan and Swakop ephemeral Rivers, the Tertiary paleochannel sediments, and Proterozoic basement aquifers. The ephemeral rivers are important because they supply groundwater downstream of the mines for agricultural use. The analysis demonstrated that the alluvial aquifers have the lowest natural radionuclide content, with the U234 concentrations ranging between 0.03 and 3.4 Bq/l, while paleochannel and basement aquifers show intermittent U234 concentrations ranging between 0.25 and 5.1 Bq/l. The groundwater in the immediate ore zones shows the highest U234 concentrations, ranging between 44.8 and 86.3 Bq/l, exceedingly higher than the WHO standards of 1 Bq/l. This study illuminates that radioactivity is a natural phenomenon and that groundwater baseline data is paramount to groundwater protection.
Ensuring the provision of sustainable water services in water-scarce humanitarian environments	F	Ward		2023	Water scarcity, Groundwater, Climate change, assessments, Monitoring, system strengthening, Resilience
Abstract Annually, UNICEF spends approximately US$1B in water, sanitation and hygiene programming (WASH), approximately half of which is spent in humanitarian contexts. In emergencies, UNICEF supports the delivery of water, sanitation and hygiene programming under very difficult programming contexts – interruptions to access, power supply and a lack of reliable data. Many of these humanitarian situations are in contexts where water scarcity is prevalent and where the demand and competition for water are increasing, contributing to tension between and within communities. While water scarcity is not new to many of these water-scarce areas, climate change is compounding the already grave challenges related to ensuring access to safe and sustainable water services, changing recharge patterns, destroying water systems and increasing water demand. Incorrectly designed and implemented water systems can contribute to conflict, tension, and migration. Ensuring a comprehensive approach to water security and resilient WASH services can reduce the potential for conflict and use water as a channel for peace and community resilience. This presents an enormous opportunity for both humanitarian and development stakeholders to design water service programmes to ensure community resilience through a four-part approach: 1. Groundwater resource assessments 2. Sustainable yield assessments (taking into consideration future conditions) 3. Climate risk assessments 4. Groundwater monitoring/early warning systems UNICEF promotes this approach across its WASH programming and the sector through technical briefs, support and capacity building.
Integration of water simulation modelling for water conservation and demand management in the mining sector (a case study)	Fanie	Botha	South Africa	2015	legislative challenges, integrated modelling, WUL
Abstract This paper outlines and presents out-of-the-box theories as examples to highlight some of the challenging restraints within the current legislative environment preventing scientists, engineers and other operational personnel to take theory into action and implementation. Key to this is the very static nature of the water use license (WUL)and associated process. The first example shows how integrated dynamic water modelling can be utilized to create an integrated water and waste management plan within the mining sector. The models developed using principles from Government Notice 704, the Best Practice Guidelines (BPGs) and the principles of water conservation and demand management. Ultimately it keeps clean and dirty water flows separate and optimises the use of dirty water in order to reduce raw/potable water off-takes through this process. The objective of these models are to optimise the water use and develop strategies to ultimately enable mines to optimize it's internal non-potable water resources therefor relieving pressure on the limited potable systems, as well as aiding surrounding communities, in which they operate, with potable water. Results from the model provides for 1 or 20 years simulation data that differs year-on-year based on numerous factors, i.e. rainfall, run of mine (ROM) feed and growing/declining surface run-off areas. The variability of the results makes it almost impossible to utilize within application documentation as it is too complex and it does not align with the application figures as required in the WUL process. This resulting in a fairly simplistic and sometimes unrealistic static model that is submitted as part of the application.
Estimation of representative transmissivities in heterogeneous aquifers	Fanie	de Lange		2015
Abstract The so-called apparent increase of transmisivity (T) or hydraulic conductivity (K) with scale is an artifact and does not exist in the field. The reason for the apparent increasing of T with scale is due to the use of the "not applicable" random log Gaussian stochastic models that are used by geohydrologists. In the petroleum field, which uses deterministic methods, the apparent increase of T with aquifer volume does not occur. Groundwater practitioners have to change their view and use models that do not show this effect. By using intuitive inspection of geological, fracture and connectivity data as well as real pumping test data, this paper shows that up-scaling must be performed with an exponential decaying function, where T always decreases with scale . Two types of heterogeneities exists namely a.) horizontal and b.) vertical. Connectivity between fractures is extremely important in both cases, but it is only in semi-confined and watertable aquifers that the vertical heterogeneities are really important (typical case of fracture dewatering) {List only- not presented}
Platinum mines will leave behind a sustainable legacy which will form a vital building block to meet future water demands	Fanie	Botha		2015	aeration and aerobic storage facilities, Nitrate
Abstract Slightly more out of the box idea is the use of anthropogenic aquifers as storage and chemical conditioners. This concept was first introduce by Eland Platinum Mine(EPM) and reported on in previous papers. At EPM water is used through a serious of natural aeration and aerobic storage facilities to reduce nitrate levels. In 2013 another group introduced pilot studies by virtue of abstraction in support of the water conservation and demand management strategy; which has proven that it could enable the operations to overcome water shortage periods and reduce pressure on Rand Water (RW). The pilot sites would deliver water into the dirty water circuit, but within five to ten years it may further be used to overcome months with zero potable water supply. . In platinum mines the more the aquifers are used the cleaner the water becomes, simply because introduced pollutants are not constant sources and country rock is mostly inert. In the future these aquifers have the potential to become larger storage facilities protected from floods and limited evaporation losses. It is foreseen that some of the mines in the western belt may have more water stored in primary aquifers than water stored within major water dams. Yields from these aquifers for individual aquifers may be up to 450 m3/hour and storage of 18 Mm3. . Why then this paper if we are already using it? The issue is that the true value of these aquifers an only be unlocked when they are used as recharging aquifers and thereby actively storing dirty water within a dirty water aquifer. Once we are able to undertake this the positive environmental gains such of environmental overflows, condition dirty water, reduction of pollution and significant reduction of the use of potable water from RW. {List only- not presented}
A changing environment focussing on drought	Fanus	Fourie	Northern Cape	2021	Drought, community supply, groundwater behaviour, Pumping
Abstract The western part of South Africa is experiencing a prolonged drought. In many cases, the effects of drought have been noticed since 2011, putting the western part of the Northern Cape under severe stress to provide water to the communities. In the past 10 years, rainfall has also decreased, and in most cases, the catchments did not receive rain to help with the recharge of groundwater. Various lessons were learned from the change in the climate and environment. But a lot can be done to minimise the impact of these changes on the water supply to communities. This paper addresses what we are noticing in the environment that impacts the way we think groundwater behaves. The changes include the change in rainfall: patterns, lines, and type of rainfall. The collapsing of boreholes with water strikes closing when being over-pumped occurs more often in the last 3 years. Pump test recommendation changes with water level change – deployment output. A combination of the factors mentioned puts more stress on groundwater resources, and a mindset change is needed to give assurance of future supply to the communities.
A Practical Guide To Conserving Groundwater Underground	Fanus	Fourie	National	2019	Conservation, Management, Groundwater
Abstract Conservation is most Academic Editor likely linked to the behaviour of the user to use less water and to use the water more efficiently. The actions will include fixing the leaking taps, toilets and pipes; the implementation of best practices; and awareness programs. All these activities are after the water is taken from the water resource. However, the question remains: "Can water be conserved while still in the resource?" Moreover, then further "What is Groundwater Conservation?" Conservation of groundwater is related to the use of groundwater at the right time and adopts a management style that suits the aquifer characteristics. By knowing when, where, and how much to pump an aquifer can enhance the performance and life of an aquifer. By understanding the different operating rules levels and how the rules influence each other, the optimal yield can be determined. Climate variability and change is having a significant impact on our groundwater resource and the way we are managing our aquifers. Cost to pump and treat the groundwater can be cut with benefits not just to the municipality but also to the community and environment. The paper will go into practical examples to understand the concept of groundwater conservation; to implement groundwater conservation at the local level and the benefits.
The National Groundwater Strategy for South Africa	Fanus	Fourie	National	2017	strategy, IWRM, Governance, risk-based approach
Abstract The paper provides an outline of the recently published National Groundwater Strategy and of the approach to its implementation. According to the National Water Resource Strategy, development of groundwater resources will be crucial for sustaining water security in the light of increasing water scarcity in South Africa. Already groundwater’s role in South Africa has undergone a major change during the water sector transformation post-1994, from an undervalued resource and a ‘private water legal status’ to a source of domestic water and general livelihood to more than 60% of communities in thousands of villages and small towns country-wide. However, there are major concerns that local groundwater resources are very poorly managed and that major aquifers are under pressure in many locations through over- abstraction, declining water levels and water quality degradation. In the light of these general challenges, there has been a recognition, world-wide, that, with increasing level of groundwater development, there has to be an incremental institutional path, moving from technical development of the resource to groundwater management and ultimately to groundwater governance as part of IWRM. This is the path South Africa is intending to follow in the development of a national groundwater strategy initiated in 2015. At the heart is an agreed strategic framework of groundwater governance and a stakeholder-driven process to roll out the framework over the next 10-20 years. Appropriate governance is particularly important for groundwater, because of its ubiquitous nature and relative ease of local access. Focus on local stakeholder involvement will be essential. Thus major issues that will have to be addressed from the beginning to encourage stakeholders to be more willing to contribute to the management efforts include proper valuation of groundwater, scientific understanding and accessible data and information and broad-based education to build social support for management. The strategy framework will address three essential levels, namely the local action level, the national/regional regulatory, planning and institutional development level and an enabling policy level. A major challenge at the enabling level is the present lack of a well-capacitated national groundwater champion to guide and coordinate the overall roll-out process. Different ways for a much greater involvement of the groundwater sector as a whole are suggested. A risk-based approach is proposed to achieve increased focus and levels of management for more stressed aquifers on a priority basis. This must be seen as a major paradigm shift from national management to facilitated local level participative management of groundwater resources within the overall IWRM framework.
Quenching A Thirsty Country	Fanus	Fourie	National	2013	Groundwater, strategy, Boreholes
Abstract Only 40% of all the available groundwater resources are developed in South Africa and the development of surface water are becoming more costly and challenging. The Minister of Water and Environmental Affairs acknowledge this and identified the need to increase the use of groundwater as one of the interventions to address the increasing water requirement of towns and communities. Over the last seven years the Department of Water Affairs developed many reconciliation strategies for the area of water management, the big metro municipalities and for the smaller towns and villages in South Africa. The reconciliation strategies entails, among other things, sustainable ways to source additional water supplies for the selected towns/metro’s or villages. Groundwater played a major role in the recommended interventions. The challenges are now the implementation of the groundwater schemes and sustainable management of the groundwater resources. Or differently put: the balancing act between selling of groundwater and the prevention of over-abstraction. The bankability of regional schemes, the credibility of groundwater as a bulk scheme source, poor management of boreholes/well-fields, institutional responsibility, acceptable quality and treatment of groundwater, still challenge the use of groundwater development. Groundwater need to play its role in addressing the future water needs of South Africa, or can it?
Using the Groundwater Level Status approach for climate Impacts	Fanus	Fourie	South Africa	2023	Groundwater level; Status; water level fluctuation; risk; climate change; recharge
Abstract South Africa is known for droughts and their effect on groundwater. Water levels decrease, and some boreholes run dry during low recharge periods. Groundwater level fluctuations result from various factors, and comparing the levels can be challenging if not well understood. Fourie developed the “Groundwater Level Status” approach in 2020 to simplify the analysis of groundwater level fluctuations. Groundwater levels of two boreholes within different hydrogeological settings can thus be compared. The “Status” can now indicate the severity of the drought and thus be used as a possible groundwater restriction level indicator. The reasons for the groundwater level or the primary stress driver can only be determined if the assessment is done on individual boreholes and the boreholes according to hydrogeological characteristics. The analysis is used to identify areas of risk and inform the authorities’ management to make timely decisions to prevent damage or loss of life or livelihoods. The applicability of this approach from a borehole to an aquifer level is showcased through practical examples of the recent droughts that hit South Africa from 2010-2018.
The Relationship Between Groundwater Governance And Management At Local Municipal Level.	Fanus	Fourie	National	2019	Governance, Management
Abstract The terms 'Management' and 'Governance' are used interchangeably when referring to groundwater such as policy, protection, operations, financial systems and infrastructure. Governance and management are not separate scales of action, but different processes. Both processes can take place together at local, regional, national or global scales. (Seward 2015). The influences from the different levels of government are also linked. Governance and management can in most case not be split into two blocks and handled separately. The degree of governance vs management differs per level of government from institution to institution. The line between governance and management is thus very flexible between the different areas/location or aquifers where groundwater is being used and protected. Some functions, responsibilities and roles are very difficult to place under governance or management alone and can fall under both. The term 'Implementation Governance' was created to describe the overlap of functions, and this also links closely to the term 'Local Level Governance' that focuses on governance at the local municipal level. The paper describes the relationship between governance and management functions at different government levels and illustrates it through five scenarios/examples of the different government organisations at the municipal level.
Researching Fracking in the Karoo: Summary of lessons learned	Fde	Lange	South Africa	2023	Challenges, Fracking, Independent, policy, Precautionary, Regulatory, Research, risks, scale, stakeholders
Abstract Research on Fracking in the Karoo basin yielded results that, if not considered “unexpected”, can be considered as “should have been foreseen”. Some aspects substantially impacting research on fracking are often overlooked when undertaking scientific research on an emotional topic such as fracking. This presentation aims to provide insights and recommendations based on the experiences and outcomes of current research on hydraulic fracturing or “fracking” in the Karoo basin of South Africa. Fracking has been a subject of significant research and debate over the past decade. Topics, each with its challenges, include 1) The scale of exploration/production extent (Site specifics), 2) Importance of robust and independent research, 3) Need for stakeholder engagement and participation, 4) The complexity of environmental risks and impacts, 5) The need for a precautionary approach, 6) Regulatory and policy challenges. Several methodologies can be relied upon to compare outcomes of different aspects of fracking research in the Karoo, such as 1) Comparative analysis, 2) Meta-analysis, 3) Stakeholder mapping and analysis and 4) Data visualisation. A combination of these methodologies can be used to compare outcomes of different aspects of fracking research in the Karoo and provide insights and recommendations for future decision-making and planning. Ultimately, the decision to allow Fracking should be based on a balanced assessment of potential risks and benefits, considering long-term impacts on the environment, economy, and communities.
Per and Polyfluoroalkyl Substances (PFAS) Groundwater Toolkit	Fern	Beetle-Moorcrof	western United States	2023	PFAS, fate and transport, Groundwater, sampling
Abstract Per and Polyfluoroalkyl substances (PFAS) are ubiquitous on our planet and in aquifers. Understanding PFAS transport in aquifers is critical but can be highly uncertain due to unknown or variable source conditions, hydrophobic sorption to solid organic aquifer matter, ionic sorption on mineral surfaces, changing regulatory requirements, and unprecedentedly low drinking water standards. Thus, a PFAS toolkit has been developed to enable decision makers to collect the hydrogeologic data necessary to understand and better predict PFAS transport in aquifers for the purpose of managing water resources. This toolkit has been tested at a significant alluvial aquifer system in the western United States, which provides water for 50,000 people. Here, the toolkit has provided decision makers with the data necessary to optimize water pumping, treatment and distribution systems. The toolkit describes (1) the design and implementation of a sentinel well network to measure and track PFAS concentrations in the alluvial aquifer over time in response to variable pumping conditions, (2) data collection used to empirically derive input parameters for groundwater fate and transport models, which include the collection of paired aquifer matrix and groundwater samples, to measure PFAS distribution coefficients (Kds) and modified borehole dilution tests to measure groundwater flux (Darcy Velocity) and (3) the use of data collection techniques to reduce cross contamination, including PFAS-free, disposable bailers and a triple-rinse decontamination procedure for reusable equipment. The PRAS transport toolkit has the potential to assist decision makers responsible for managing PFAS contaminated aquifers.
Hydrostratigraphy of the Bauru and Guarani Aquifer Systems in the central region of the State of São Paulo (Brazil)	Fernando	Barreto	Brazil	2023	3D Modelling, Bauru Aquifer System, Guarani Aquifer System, hydrostratigraphy
Abstract The Guarani Aquifer System (SAG) is the main public water supply source in Bauru City (Brazil). It mostly consists of sandstones and is a confined unit of fossil waters (~600 thousand years); therefore, it is a non-renewable and finite resource. SAG is overlaid by the Bauru Aquifer System (SAB), predominantly consisting of sandstones, siltstones, and mudstones, and is essential for private water supply in the municipality. In recent decades, constant drops in water levels in SAG and increases in contaminant loads in SAB have been observed in production wells, generating the need to understand the geometry of those aquifer systems. This work presents the preliminary results of the analysis and review of hydrogeological and geophysical data from 59 deep wells and 3D geological modelling using Leapfrog Works® to represent a conceptual model of the study area. SAG has a thickness of up to 356 m in the wells and is represented, from bottom to top, by Teresina, Piramboia, and Botucatu formations. In the north and northeast regions, SAG is covered by a layer of basalts from the Serra Geral Aquifer System (SASG) with a thickness of up to 190 m. The thickness of SASG is variable (or even null) due to the action of important faults with vertical displacements that created structural windows in the region. SAB covers the Araçatuba (basal portion), Adamantina (144 m), and Marília (65 m) formations. The lower contact of SAB is made with SASG or SAG (central region). Project funded by FAPESP (2020/15434-0).
Estimating The Water Make Of A Rehabilitated Opencast Coal Mine In Mpumalanga	Francois D	Fourie	Mpumalanga	2013	opencast coal, decanting
Abstract After a period of heavy rainfall in 2006, pit water from a rehabilitated opencast coal mine in the Mpumalanga Province started decanting, causing impacts on the adjacent agricultural land and river system. Various actions have since been taken to manage the pit water, including construction of contour berms to prevent clean water entering the ramps, construction of levees and dam walls to increase the decant level, irrigation of mine water on the rehabilitated areas of the pits, disposal of pit water in nearby pans, recirculation of pit water by means of pumping between the various voids, controlled release of pit water to the river system, and construction of a pipeline to pump pit water to a nearby colliery where there is a demand for process water. For the purpose of mine closure, a water management plan was required for which an estimate of the water make of the colliery was needed. The water make was estimated by using measured quantities (rainfall data, pumping rates, dam water levels) and estimated quantities (evaporation from open water bodies), while making a number of simplifying assumptions. This approach revealed that the conventional method of estimating the water make as a percentage of rainfall recharged through the spoils, significantly underestimates the volumes of water that need to be dealt with at the colliery. Large volumes of groundwater appear to be entering the pits along preferential pathways connected to recharge zones at higher elevations, contributing to the water make of the colliery.
Characterisation And Protection Of Deep Aquifers In South Africa: Consolidation Of Data Sources	Francois D	Fourie		2017	Deep aquifers, data sources
Abstract This paper describes the results of study aimed at consolidating the available data sources on deep aquifers and deep groundwater conditions in South Africa. The study formed part of the larger WRC Project K5/2434 (Characterisation and Protection of Potential Deep Aquifers in South Africa). Since very little is known about the aquifer conditions below depths of 300 m, all groundwater information from depths greater than 300 m was considered to represent the deep aquifer systems. Various confirmed and potential sources of data on deep aquifers and groundwater conditions were identified and interrogated during this study, namely: 1. Boreholes of the International Heat Flow Commission (IHFC). The IHFC database indicates the location of 39 deep boreholes ranging in depth from 300 to 800 m, with an average depth of 535 m. 2. The Pangea database of the International Council for Science (ICSU). The Pangea database has information on 119 boreholes in South Africa, of which 116 are deeper than 300 m. 3. A database on deep boreholes at the Council for Geoscience (CGS). This database contains information on 5 221 boreholes with depths exceeding 300 m. 4. Information on the deep SOEKOR boreholes drilled during the 1960s and 1970s (at least 38 boreholes). 5. Information on deep boreholes from the database of the Petroleum Agency SA. 6. The National Groundwater Archive (NGA) of the Department of Water and Sanitation (DWS). 7. Information derived from the thermal springs in South Africa. 8. Boreholes drilled as part of the Karoo Research Initiative (KARIN). 9. Information on the locations and depths of underground mines in South Africa. Information on the occurrence of deep groundwater could potentially be obtained from these mines. The study shows that, although information on a vast number of deep groundwater sites is listed in the various databases, the data relevant to the geohydrological conditions are scant at most sites. This paucity of geohydrological data implies that the deep aquifers of South Africa are currently poorly understood.
Characterisation And Protection Of Deep Aquifers In South Africa: Characterisation	Francois D	Fourie		2017	Deep aquifers, Aquifer characterization, groundwater flow, Groundwater Quality
Abstract This paper describes the characteristics of the deep aquifer systems in South Africa as derived from the available data. The study formed part of the larger WRC project K5/2434 (Characterisation and Protection of Potential Deep Aquifers in South Africa). A review of the available literature relevant to potential deep aquifers in South Africa was done to allow characterisation of these aquifer systems. In addition, data obtained from the geological logs of the SOEKOR and KARIN boreholes were considered. This paper focuses on deep aquifers in 1) the Karoo Supergroup, 2) the basement and crystalline bedrock aquifers, 3) the Table Mountain Group, 4) the Bushveld Igneous Complex and 5) the dolomites of the Transvaal Supergroup. From the available data the deep aquifer systems are described in terms of the following characteristics: lithology, occurrence, physical dimensions, aquifer type, saturation level, heterogeneity and degree of isotropy, formation properties, hydraulic parameters, pressurisation, yield, groundwater quality, and aquifer vulnerability. The results of the study show that the deep aquifer systems of South Africa are generally fractured hard-rock aquifers in which secondary porosity was developed through processes such as fracturing and dissolution. The primary porosity of most of the rocks forming the aquifers is very low. Apart from the dolomite aquifers, most of the water storage occurs in the rock matrices. Groundwater flow predominantly takes place along the fractures and dissolution cavities which act as preferential pathways for groundwater migration. The aquifers are generally highly heterogeneous and anisotropic. The deep aquifers are generally confined and associated with positive hydraulic pressures. The groundwater quality generally decreases with depth as the salinity increases. However, deep dolomite aquifers may contain groundwater of good quality. Due to the large depths of occurrence, the deep aquifer systems are generally not vulnerable to contamination from activities at surface or in the shallow subsurface. The deep dolomite aquifers are a notable exception since they may be hydraulically linked to the shallower systems through complex networks of dissolution cavities. The deep aquifers are, however, very vulnerable to over-exploitation since low recharge rates are expected.
Groundwater Resource Development targeting major fault zones In Banded Iron Formations (BIF) for Augmentation of the Vaal Gamaga	Frans	Wiegmans	Northern Cape	2015
Abstract The mineral rich Northern Cape Province produces 84% of South Africa's iron ore, while the Kalahari basin holds 92% of the world's high grade manganese deposits, with diamond and lime mining operations to a lesser degree. Mining expansion programs and new mines planned in the Northern Cape drive the region's economic development and growth strategy. The planned mining expansion depend on water being available for mining water needs and related increased demands for domestic water supplies. Current water supplies consist of local groundwater resources (boreholes and mine dewatering) and bulk water supply from the Vaal Gamagara (VGG) Pipeline Scheme. In 1992 the Kalahari East water supply pipeline was incorporated to supply domestic and stock water to an area of approximately 1.4 million ha. The VGG scheme consists of 370 km pipes, was built in the late sixties and is nearing its useful life expectancy. Increased water supply interruptions are being experienced while operating at capacity. The pipeline has the capacity to convey and import water of approximately 15 million m3/a into the D41J and D41K quaternary catchments. Water demand projections show an increase to 40.1 million m3/a in 2030. Various options were investigated to upgrade the VGG water supply scheme. One option considers groundwater resources to augment the water from the Vaal River from four indentified target areas (SD1 to SD4). Major fault zones in Banded Iron Formations (BIF) are targeted for groundwater resource development in the SD4 area, located east of Hotazel. This area is largely covered by Quaternary age sand and located near the endpoint of the VGG scheme and therefore prioritized as investigation area. The primary objective of the hydrogeological investigation was to identify the existence of exploitable resources for additional source development. Secondary objectives were to assess the contribution groundwater can make to augmenting pipeline water; providing a source to an area and thus diminish reliance on the pipeline; and providing an independent source, which could prevent the need for pipeline extensions. The paper will discuss the use of an airborne magnetic and Time Domain Electromagnetic's (TDEM) survey combined with gravity ground surveys as a key success factor in adding to the geological and structural information of the area. The paper will also present the results of exploration drilling (> 60 boreholes) over a large area and related borehole test pumping with water sampling to identify a sustainable and potable water supply of 2.5 million m3/a.
Effective Open Cast Pit Dewatering And Groundwater Management At Sishen Mine By Utilizing Software And Technology.	Franszo	Faul	Sishen Mine	2019	dewatering, software
Abstract It's been said that you cannot manage what you cannot measure. This is especially true with groundwater management; where we have limited data allowing us to 'see' the underground source. All over the world, people are spending aquifers full of money (bucket loads) on monitoring programmes and hydro census's. They capture borehole locations, water levels, abstraction rates, rainfall measurements and water quality analysis, then typically store the product, the deliverable, their valuable data, in a massive amount of spreadsheets. They have measured, but struggle to manage effectively because the data has not been stored in a centralised, consolidated fashion. Join us for a journey through Dagbreek, an open cast pit at Sishen mine, one of the largest open cast iron ore pits in the world and certainly part of the biggest dewatering project in South Africa. See how Sishen utilised technology to eliminate manual, paper-based data collection and spreadsheets. See how they utilised a cloud-based information management system to centralise and consolidate their data before transforming the data into valuable visualised information. See how this is equipping Sishen's decision makers with easy to interpret and up-to-date information, empowering them to make more effective operational and management decisions about their dewatering and groundwater management strategy
The Management of Groundwater resources using GIS/Cartography splay)	Freda	Jonck		2015
Abstract The Department of Water Affairs and Sanitation is the custodian of the Water Resource in South Africa. The Western Cape Regional Office, Geotechnical Service Sub Directorate, is responsible for management of groundwater resources in two Water Management Areas (WMA), Olifants Doorn-Berg and Breede-Gouritz. Twenty-nine monitoring routes comprising 800 sites in total are monitored across the Western Cape Region. The purpose of this paper is to create awareness of groundwater related databases and the type of information products used in assessing the status of data bases and groundwater resources. This is to assist and support the scientists, technicians, managers, external stakeholders and/or general public. The main question that needs to be answer is: "What is the current groundwater data management situation in the Regional office?" With the GIS as platform, geographical information was generated from existing data bases to answer questions such as, what is being monitored, where is it being monitored, who is monitoring it, why is it being monitored and when is it being monitored? These questions are applicable to the Region, Water Management Areas, the monitoring route and geosites. Graphical time-series information generated from available data, in combination with the generated geographical information, showed the gaps, hot spots and what is still needed for all the facets of groundwater management (from data acquisition to information dissemination) processes. The result showed the status of data bases, need for data in areas of possible neglect, training gaps, inadequate structure and capacity, instrumentation challenges, need for improvement of commitment and discipline, as well as many other issues. The information generated proves to be an easy tool for Scientists, Technicians and Data Administrators to assist them to be on top of the groundwater resource management in their area of responsibility. The expansion of the use of GIS as a groundwater management tool is highly recommended. This will ensure better understanding of the resource: "The Hidden Treasure".
GIS and Groundwater Monitoring	Freda	Jonck	Western Cape	2017	monitoring network, resource assessment
Abstract The Department of Water Affairs and Sanitation is the custodian of the Water Resources in South Africa. The Western Cape Provincial Office, Geotechnical Services (Geohydrology) Sub Directorate, is responsible for management of groundwater resources in two Water Management Areas (WMA), Berg Olifants and Breede- Gouritz. Thirty-eight monitoring routes comprising 700 sites in total are monitored across the Western Cape Province. The purpose of this paper is to show the use of GIS as a management tool for groundwater monitoring in the Western Cape. This is to assist and support the scientists, technicians, managers, external stakeholders and/or general public. The main question that needs to be answered is: “What is the current groundwater monitoring and data management situation in the Provincial office” With GIS as platform, geographical information was generated from existing data bases to answer questions such as, what is being monitored, where is it being monitored, who is monitoring it, why is it being monitored, when is it being monitored, are instruments installed, what instruments are installed, what equipment is involved and what energy source is used? These questions are applicable to the Region, Water Management Areas, the relevant monitoring route and geosites. Generated geographical information showed the gaps, hot spots and what is still needed for all the facets of groundwater management (from data acquisition to information dissemination) processes. The result showed the status of data bases, need for data in areas of possible neglect, training gaps, inadequate structure and capacity, instrumentation challenges, need for improvement of commitment and discipline, as well as many other issues. The information generated proves to be an easy tool for Scientists, Technicians and Data Administrators to assist them to be on top of the groundwater resource management in their area of responsibility. The expansion of the use of GIS as a groundwater management tool is highly recommended. This will ensure better understanding of the “The Hidden Treasure” resource.
Modelling recharge in an opencast coal mining environment, applying model parameters on a catchment scale.	Freek	van Devnter		2015
Abstract The provision, usage and discharge of water resources are major concerns for coal mines, both underground and opencast. Water resources in a coal mining environment will often account for a significant portion of the daily operational cost. In order to cut costs, the mine will often collect as much runoff as possible to recycle for future use. This on-going recycling of site water and management of the resource demands a complete site water balance model in order to understand the dynamics of the resource within the boundaries of the mine. To improve the understanding of the dynamics of the resource on a much larger scale, and the effect it will have on recharge in an open cast coal mine environment, one must consider alternative modelling approaches which can compensate for such conditions. This amounts to describing recharge as a modelling component in a physically based distributed model. The main goal of this project is to calculate recharge into the main pit at this specific colliery by applying parameters on a quaternary catchment scale. The colliery is located just west of the town of Ogies, Mpumalanga on the peripheral region of the quaternary catchment B20G. The physiography of the quaternary catchment B20F is described as a central Highveld region gently sloping to the north. The geohydrological modeling application MIKE SHE (developed by DHI) was used to develop a fully integrated catchment model. The model was created mainly to simulate the impact of human activities on the hydrological cycle and hence on water resource development and management. Different modules of MIKE SHE that was used during the modelling stage include saturated- and unsaturated flow and a small degree of overland flow. Key words: Mpumalanga, MIKE SHE, recharge
Characterization of groundwater dynamics to identify the risks of flooding of the sewerage network of the urban communities of Lens-Liévin (northern France)	G	Picot-Colbeaux	France	2023	aquifer, Groundwater, groundwater inflow, hydrodynamic modelling, piezometry, sewerage network, urban hydrogeology
Abstract The interactions between groundwater and the sewerage networks of the Lens-Liévin urban communities, located in the north of France, locally lead to non-compliance in the operation of the network and the wastewater treatment plants, questioning the city’s economic development policy. Indeed, the infiltration of groundwater inflow in the sewerage network could be the cause. Based on the piezometric measurements carried out in 2022, the surface elevation of the groundwater table is carried out using a kriging approach. The comparison of altitudes between network position and piezometry made it possible to identify the pipes most at risk of the infiltration of groundwater inflow and correspond to those indicated as non-compliant by network managers according to the national decree. Outside this period, the network vulnerability indicators are defined based on simulated piezometry by a 3D hydrodynamic model of the chalky hydrosystem (MARTHE code) established in a transient state. For two past extreme situations, the network would have been flooded at 1.20% in the dry period (1997) and up to 8.30% in the wet period (2001), highlighting the existence of a part of the network systematically flooded. Using the hydrodynamic model according to different prospective scenarios makes it possible to anticipate the actions deployed on the network to guide management and adaptation solutions. However, a modelling methodology that considers the feedback between the dynamics of the groundwater and the flows passing through the networks remains to be developed.
Sustainable establishment of localised groundwater supply systems at critical infrastructure for disaster preparedness	G	Kode	South Africa	2023	Western Cape Province, business continuity planning, critical facilities, disaster planning, localised groundwater supply systems, water resilience
Abstract Given the challenging global water outlook due to climate change and urbanisation, there is a heightened necessity for greater water resilience at critical facilities to tackle water disasters or disasters that lead to water crises. In 2017, the Western Cape Province of South Africa experienced an extended drought with the risk of acute water shortages. The Western Cape Government (WCG) developed business continuity plans and implemented a programme to ensure water supply to certain critical service delivery facilities, utilising the strategy of developing localised groundwater supply systems. The case study research of the WCG program enabled the development of an evaluation framework that assessed this strategy’s effectiveness in improving water resilience levels at critical facilities. From the lessons learnt in the WCG programme, the research also crystallised the critical success factors in sustainably implementing this strategy. The research showed that this is an effective strategy for its purposes and provides both current and future disaster preparedness planners with an improved understanding of the levels of water resilience achievable through this strategy and the methodology to achieve it best.
Netherlands National Groundwater reserves: 3D mapping and development of management policies as part of a multilevel strategy to secure water supply for disasters and the far future.	G	Nijsten	The Netherlands	2023	3-D mapping, Multi-layer governance, National fresh-salt groundwater model, Water supply strategies
Abstract The Netherlands produces about 2/3 of drinking water from groundwater. Although there is seemingly abundant groundwater, the resource needs to be carefully managed and used wisely to safeguard the resource for future generations and in case of disasters whilst also preventing negative impacts from groundwater extraction on other sectors such as nature. Provincial governments are responsible for the protection of existing groundwater abstractions for water supply against pollution. To secure groundwater resources for the future, two additional policy levels have been introduced: Provincial governments have been made responsible for mapping and protecting Additional Strategic Reserves. These allow for additional groundwater abstractions to meet growing demands in coming decades (horizon 2040/2050). The National Government is responsible for mapping and protecting the National Groundwater Reserves (NGRs) as a third level of resource protection. NGRs serve multiple goals: to protect natural groundwater capital for future generations, to provide reserves for large-scale disasters affecting water supply and to provide reserves for possible use as structural water supply in the far future (horizon 2100 and beyond). NGRs are being delineated in 3D using detailed existing geological models and the Netherlands’ national (fresh-saline) hydrological model. The dynamics of the groundwater system are analysed through scenario analyses. Reserves for potential structural use are selected such that negative impacts on nature are prevented if future abstractions are to be realised. The policies being developed must balance interests of water supply against other sectoral interests such as the green-energy transition with increased use of geothermal energy and aquifer-thermal-energy-storage.
Comparison of Topographical and Seasonal Variation of Geochemical Parameters in the Kuils River and Steenbras River	G.D.	Rezelman	Western Cape	2017	geochemical parameters, Topographical Variation
Abstract Water resources are a great concern in South Africa, more specifically the Western Cape. Therefore, a need has developed to understand the processes that may affect these precious resources. In the Western Cape large proportions of these resources are in the form of streams originating in untouched mountainous areas. However, as these streams continue towards the ocean they are faced by many threats. Alien vegetation, the destruction of river beds and abstraction from streams and boreholes threaten to dry up these resources. Additionally, pollution from fertilizers, sewage treatment plants as well as urban and industrial run-off contaminate these resources. The influx of pollutants, such as fertilizers, usually varies between seasons as it is only applied at certain times of the year. However, pollutant concentrations are not only linked to riparian land-use but are largely affected by climate changes as well. Processes such as surface run-off, along with first flush events and dilution control the nutrient concentrations in the streams. Although water is a renewable resource, it is not replaceable. This project will look at the streams’ self-purification potential. This refers to the processes within the rivers that lead to an in situ reduction of contaminants and pollutants. For example, contaminants and pollutants in rivers can be reduced by particle settling, plant and microbial uptake as well as chemical processes such as redox reactions and complex formation. For this project, pollution will be categorized into two different groups: nutrients and major ions from both point sources and non-point sources. The relevant nutrients analysed in this study are: nitrate, ammonium, phosphate and sulphate; and the major ions analysed are: Calcium (Ca), Sodium (Na), Potassium (K), Aluminium (Al), Iron (Fe) and Manganese (Mn). These will be analysed in conjunction with several physico-chemical parameters: temperature, pH, conductivity, total dissolved solids (TDS), salinity, oxidation reduction potential (ORP) and alkalinity. Analysing these parameters will allow us to measure the effects these processes have on pollution concentrations in the rivers and how climate changes facilitate these processes. For this study, the polluted Kuils River will be analysed and compared to the Steenbras River, which lacks major direct contaminants. This stream will this mainly serve as a ‘control’. Since this study will only be completed at the end of 2017, full conclusions have not been drawn yet. Therefore, this paper will highlight the findings thus far.
Characterising the Soils of the Karoo: Implications for Groundwater Resource Management	Gaathier	Mahed	Karoo	2019	Poster, hydraulic conductivity, recharge, preferential flowpaths, tracer tests
Abstract The aim of the following study was to characterise the soils of Sutherland, located in the Northern Cape of South Africa. This was completed in order to shed light on possible pathways for infiltration and understand the ultimate impact on groundwater resources. Therefore, the relationship between the soil characteristics and infiltration was explored. To achieve this, field work was conducted whereby soil profiles were exposed in order to examine the subsurface characteristics of the soil and map the soil types. Thereafter, infiltration tests were taken randomly across the terrain in order to determine the in-situ properties of the soils in the region. Dye tracer tests were conducted on two plots of 1m2 within the study area, to determine the preferential flow paths and heterogeneities within the area. Field observations, as well as dye tracer tests, indicate a low clay content at the surface. This could be attributed to high wind velocity. Finally, it is shown that local river beds are hydraulically conductive due to the coarse nature of the underlying gravel. Therefore these strips of land need to be protected in order to avoid possible contamination of the already limited groundwater supplies in the region.
Groundwater Sampling Errors: The Missing Link in the Broken Chain	Gaathier	Mahed	Karoo	2019	Sutherland, measurement uncertainty MU, theory of sampling TOS, chain of custody, hydrogeochemical processes
Abstract A hydrogeochemical analysis of multiple samples stemming from two fractured rock aquifers in the Karoo geological formation of South Africa was undertaken. The samples were taken using various sampling methods in numerous locations over varying time frames. The ion error balance for the groundwater samples from the previously mentioned secondary aquifers is further analysed. Graphical representation of the data, which includes a piper plot, gives insight into the groundwater geochemistry. Conclusions drawn highlight the precautionary measures to take into account when sampling in fractured rock aquifers in a South African context. The future recommendations include suggestions related to the entire chain of sampling in the context of the theory of sampling and measurement uncertainty for fractured rock hydrogeology in particular.
Radical evolution of the Geneva transboundary aquifer agreement: an example for the sustainability of TBA governance?	Gabriel	de los Cobos	Switzerland	2023	Geneva aquifer, MAR, Climate change, Governance, transboundary aquifer agreement
Abstract The Geneva aquifer is internationally recognized for its transboundary resource management agreement between Switzerland and France, described as the first groundwater management agreement in the world. Signed in 1978 and renewed in 2008, this agreement on managing a shared underground resource has long been an example for establishing other agreements worldwide, particularly by UNESCO and its hydrological program via the TBA commission of the IAH. Like many countries worldwide, Switzerland and France experienced a critical summer of 2022 concerning the use of water resources, both surface and underground. The system applied in the cross-border agreement for using the aquifer involves French participation in the costs of managing aquifer recharge (MAR), depending on the total pumping. It shows that the French part, having consumed more water to compensate for the extreme drought of 2022, has seen its bills increase considerably. Development plans show that the population of Greater Geneva will increase considerably by 2030-2040, requiring significant medium-term water availability (30% additional water). Therefore, the French institutions’ political leaders have formally asked the authorities of the canton of Geneva to review the conditions linked to the quotas and calculation methods included in the 2008 agreement. A new agreement could be a real example of positive cross-border coordination for decision-makers finding themselves in a blocked or even conflicting situation due to differences in managing a shared resource revived by the effects of climate change.
Modelling groundwater recharge in the Upper Vaal River Catchment.	Gaelene	Kramers	Gauteng	2015
Abstract At a regional scale, groundwater recharge is often calculated using surface water models. Precipitation and surface water runoff are easier to measure than groundwater recharge, and evapotranspiration can be estimated with relative accuracy using indirect methods. In modelling, surface water measurements can be used for calibration, and groundwater is the residual term in the water balance of the catchment. This can give a good indication of regional trends, but provides limited scope for the accommodation of groundwater system characteristics and recharge processes. Recently, much research has been focused on the interaction of surface and groundwater models. The coupling of physically based surface and ground water models allows for calibration of the model using both surface and groundwater data while providing scope for improved insight into the processes which define the interaction of groundwater with the rest of the water cycle. For example: stream discharge, interflow, preferential flow through the unsaturated zone and interaction with surface water retained in dams and wetlands. One such model is GSflow (United States Geological Survey), which we are applying to the Upper Vaal Catchment. This model integrates the surface water model PRMS (Precipitation-Runoff Modelling System) with MODFLOW (Modular Groundwater Flow model). The model is initially being calibrated at quaternary catchment scale, starting with the surface water components and later adding the groundwater system. The quaternary catchment is subdivided into smaller, topologically defined hydrological response units. This scaling allows for a better understanding of how well the characteristics of the units are represented in the physical processes incorporated into the model, so that ultimately the sensitivity analysis can incorporate these processes. The results will be compared to current work on recharge being carried out using GRACE data and previous work done in the same area. Once the entire model has been calibrated, there will be scope to calculate future scenarios, allowing for climate and land-use changes. A brief overview of existing work as well as methods and initial results and sensitivity analysis will be presented.
Monitor and determine local groundwater impacts from increased mining activities in the Kalahari iron manganese field of the Northern Cape, South Africa.	Gawie	van Dyk	South Africa	2023	aquitards, environmental impacts on groundwater, increased water demand, Monitoring, primary aquifers, reduced recharge
Abstract The Kalahari iron manganese field (KIMF) in the Northern Cape, South Africa, was historically exploited by only three mines, with Hotazel the only town and the rest of the area being largely rural, with agricultural stock/ game farming the major activity. Since 2010, mining activities have increased to more than 10 operational mines with increased water demand and environmental impacts on groundwater. The area is within catchments of the Matlhwaring, Moshaweng, Kuruman and Gamogara rivers that drain to the Molopo River in the Northern Cape. All the rivers are non-perennial, with annual flow occurrence in the upstream areas that reach this downstream area once every 10 years. The area is semi-arid, with annual evaporation nearly five times the annual precipitation. The precipitation is less than 300mm, with summer precipitation in the form of thunderstorms. Vegetation is sparse, consisting mainly of grasslands, shrubs and some thorn trees, notably the majestic camel thorns. The Vaal Gamagara Government Water Supply Scheme imports 11 Ml/d or 4Mm3 /a water for mining and domestic purposes in the KIMF section. The area is covered with Kalahari Group formation of 30 to 150 m thick with primary aquifers developed in the basal Wessels gravels and Eden sandstones for local use. The middle Boudin clay forms an aquitard that isolates and reduces recharge. Water levels range from 25 to 70m, and monitoring indicates local dewatering sinks and pollution. This study will report on the water uses, monitoring and observed groundwater impacts within the current climatic conditions.
Groundwater Remediation In The Klerksdorp Goldfields	Gawie	van Dyk	Klerksdorp	2013	Groundwater
Abstract Gold mining activities over the past 60 years in the Klerksdorp goldfield produced saline mine drainage that polluted water. Oxidation of sulphide material in tailings storage facilities, waste rock dumps and extraction plants is mobilised to produce saline mine drainage with sulphate, minor salts and metals that seep to the groundwater and ultimately into surface water resources. Water regulation requires mines to prevent, minimise/reduce or eliminate pollution of water resources. The waste philosophy has matured from tolerate and transfer to treat and termination of pollution sources. The impact of the pollution was determined and possible technologies to treat the impact were evaluated. Source controls with proper water management by storm water management, clean dirty water separation, lined water conveyance structures and reduced deposition of water on waste facilities are crucial. The aquifer character determines the possible remediation technology. From the possible technologies phytoremediation, physical interception and re-use of this water was selected. In future possible treatment of the water would be considered. This paper explain the strategy and report on the phased implementation of these plans and the expected results. The establishment of 500 ha of woodlands as phytoremediation, interception trenches of 1 000 m, 38 interception boreholes and infrastructure to re-use this water is planned. The total volume of 15 Ml/day would be abstracted for re-use from the boreholes and trenches. The woodlands can potentially attenuate and treat 5 Ml/day. The established woodlands of 150 ha prove to be successful to intercept diffused seepage over the area of establishment and reduce the water level and base flow. The two production interception well- fields that are abstracting 50 and 30 l/s, respectively , indicate a water level decline of between 2 to 14 m, with regional cones of depression of a few hundred meters to intercept groundwater flow up to a 20 m depth. Predictions from groundwater modelling indicate that these schemes can minimise pollution during the operational phase and protect downstream water resources. Predictions from modelling indicate that the pollution sources need to be removed to ensure long-term clean-up to return the land to safe use. The gold and uranium prize is securing the removal of the sources through re-processing of the tailings and waste rock dumps. After removal of the sources of pollution, the remediation schemes would have to be operated for 20 years to return the groundwater to an acceptable standard of stock watering and industrial water use. The water quality is observed by a monitoring network of approximately 100 observation boreholes.
Turning The Tide - Curbing Groundwater. Over-Abstraction In The Tosca-Molopo Area, South Africa.	Gawie	Van Dyk	Tosca-Molopo Area	2019	over-abstraction
Abstract Note: This case study was submitted and reported in the Publication Advances in Groundwater governance. The demand on fresh water has increased to such an extend that supply cannot keep up with demand, especially in areas where desalination of seawater is not an option. There is a large gap between the water user, the water supplier and the capacity of the resource/s. The water user sees it as his/her right to be provided with clean water in sufficient volumes to sustain their most basic needs.At the same time people want higher levels of service, especially where sanitation is concerned. The recent droughts in Cape Town and in Port Elizabeth have put significant focus on groundwater and we've seen uncontrolled drilling for groundwater reaching new heights, which is a problem on its own. We can no longer afford not to bring the groundwater user into the water planning cycle, so that the users, on all levels of society, can be educated to understand that the quantity and quality of fresh water (ground -and surface water) is limited and dependent on recharge from rainfall, size of the catchment, topography and all that takes place on the surface. This education must be specific to a target audience and must take into account the existing knowledge and understanding of the user profile. As an example, a case study will be discussed where there are large groundwater users operating within the upper parts of a catchment, followed by municipal abstractions and private abstractions within the central parts of the same catchment. Four profiles of users are therefore present: (1) large-scale irrigation by farmers, (2) large-scale municipal abstractions, (3) private residents and (4) formal / informal settlements, with the latter probably competing for top pot in terms of water use, with the irrigation. They key deliverable of the presentation / paper will be to (1) make people aware of the problem/challenge, and (2) suggest ways to bridge gaps and get all users and service providers to work together to save water and to understand that there are limits to the quantities available.
Remediation of Groundwater at AngloGold Ashanti South Africa	Gawie	van Dyk		2015
Abstract Gold Mining activities the past 60 years at AngloGold Ashanti polluted the groundwater underlain by 4000 ha of land at the Vaal River and West Wits operations in South Africa. Sulphide material in Tailings Storage Facilities, Waste Rock Dumps and extraction plants produce Saline Mine Drainage with Sulphate, minor salts and metals that seep to the groundwater and ultimately into surface water resources. Water regulation requires mines to prevent, minimise/ reduce or eliminate pollution of water resources. The waste philosophy has matured from tolerate and transfer to treat and termination of pollution sources. The impact of the pollution was determined and possible technologies to treat the impact were evaluated. Source controls of proper water management by storm water management, clean dirty water separation, lined water conveyance structures and reduced deposition of water on waste facilities is crucial. The aquifer character determines the possible remediation technology. From the possible technologies phytoremediation, physical interception and re-use of this water was selected. In future possible treatment of the water would be considered. This paper explain the strategy and report on the phased implementation of these plans and the expected results. The establishment of 750 ha of woodlands as phytoremediation, interception trenches of 1250 m, 38 interception boreholes and infrastructure to re-use this water in 10 water management areas is planned. The total volume of 15 Ml/day would be abstracted for re-use from the boreholes and trenches. The woodlands can potentially attenuate and treat 5 ml/day. The established woodlands of 150 ha proof successful to intercept diffused seep over the area of establishment and reduce the water level and base flow. The 2 implemented trenches of 1000 m indicate a local decline in the water level with interception of shallow groundwater within 1-2 m from surface. The 2 production interception well fields abstracting 50 and 30 l/s respectively indicate a water level decline of between 2 to 14 m with regional cones of depression of a few hundred meters to intercept groundwater flow up to 20 meter. Predictions from groundwater modelling indicate that these schemes can minimise pollution during the operational phase and protect downstream water resources. Predictions from modelling indicate that the pollution sources need to be removed to ensure long term clean-up to return the land to save use. The gold and uranium prize is securing the removal of the sources through re-processing of the tailings and waste rock dumps. After removal of the sources of pollution the remediation schemes would have to be operated for 20 years to return the groundwater to an acceptable standard of stock watering and industrial water use. The water quality is observed by a monitoring network of approximately 100 observation boreholes.
Development Of The Training Manual For Groundwater Resource Management And Groundwater Governance For Municipalities In South Africa	George G	Molaolwa	South Africa	2017	Municipalities, Training manual, Training needs assessment
Abstract In order to establish sound groundwater resource management within towns and Municipal areas the development of a training manual on groundwater resource management and groundwater governance for Municipalities is of utmost importance. A Training Manual can be extensively used for capacitating municipal official, technicians, managers, and decision-makers, as well as communities where villages and towns are partially or solely reliant on groundwater resources. Increased knowledge and skills will not only lead to more effective groundwater resource management, but also to more sustainable groundwater use and protection of groundwater resources. This also forms part of provisions made by the National Water Act 1998 (Act 36 of 1998). Before a training manual can be compiled, training needs assessments of all reachable training institutions in South Africa and Free State Municipalities and Northern Cape Municipalities as identified as pilot areas in the proposal of the Training Manual for Groundwater Resource Management and Groundwater Governance for Municipalities in South Africa needed to be performed. Training needs assessment determines if a gap exist regarding available training and training needs on Groundwater Resource Management and Groundwater Governance. If a gap exists then it proofs that the development of a Training Manual on Groundwater Resource Management and Groundwater Governance for Municipalities in South Africa is required, as well as the accessibility to such a training course is of utmost importance.
Potential Impacts Of Fracking On Groundwater In The Karoo Basin Of South Africa	Gerrit	Van Tonder	Karoo	2013	potential impact
Abstract Determining impacts associated with the production of shale gas in the semi-arid Karoo on groundwater is vital to people living in the Karoo. On the one hand shale gas can be a game-changer for energy supply, but on the other it may have a devastating effect on the environment. Knowing the potential impacts of shale gas mining beforehand, the government can set appropriate regulatory protocols and tools in place to mitigate potential risks. This paper describes research done on the potential impact that hydraulic fracturing could have on groundwater in the Karoo. A wild card that only exists in the Karoo Basin of South Africa is the numerous dolerite intrusions. These dolerite structures are associated with relative high-yielding boreholes because of the fractured contact aureole that exist between solid dolerite and the adjacent Karoo sediments. Compromised cement annuli of gas wells are the major preferential flow paths along which methane and fracking fluid can escape into shallow, freshwater aquifers. This study focused solely on the impact of compromised cement annuli of gas wells. The Karoo Basin is under artesian conditions which imply that any pollutant will always try to migrate upwards in the Karoo. The hot-water springs in the Karoo indicate that upward velocities of water are relatively high (the spring water take only days to travel from deep down to the surface). The cubic law was used to estimate potential upward leakage rates from gas wells (during production, but after cessation thereof as well, when pressures will rebuild because of artesian behaviour of the Karoo formations). Potential leakage rates along faulty annuli of a well can vary between a value close to zero to two liters per second in the case of an aperture of 0,5 mm. These leakage rates were used as input to a 2D numerical groundwater flow and mass transport model. The 2D model was run for 30 years and the movement of pollution from the gas wells on the pad simulated. The model indicates that an area of 300 ha could be contaminated over a period of 30 years in a downstream groundwater flow direction. If an abstraction borehole drilled along a fault zone or a dyke, intersecting the fracked reservoir, is introduced into the model, results predict that the pollutant will reach the borehole in less than two months if the borehole is situated six kilometres from the well-pad. The total impact that fracking will have on the groundwater in the Karoo, is a function of the total area that will be fracked. The outcomes of this research clearly show that fracking in South Africa cannot be done in the same way than it is currently done worldwide. A rule that will force gas companies to disclose fracking fluid contents is non-negotiable. Companies should also be required to measure pressures in the fracked gas reservoir after closure. An additional requirement to enforce sealing of the entire fracked reservoir with a very dense material like bentonite or a mud with a very high density to capture the fracking fluids deep down in the gas reservoir should not be negotiable.
Estimation Of Representative Transmissivities In Heterogenous Aquifers	Gerrit	van Tonder	National	2013	transboundary aquifers, hydraulic conductivity
Abstract The so-called apparent increase of transmisivity (T) or hydraulic conductivity (K) with scale is an artifact and does not exist in the field. The reason for the apparent increase of T with scale is due to the use of the “not applicable” random log Gaussian stochastic models that are used by geohydrologists. In the petroleum field, where deterministic methods are applied, the apparent increase of T with aquifer volume does not occur. Groundwater practitioners have to change their view and use models that do not show this effect.
Hydraulic Fracturing Of Coal Bed Methane In The Springbok Flats	Gerrit	van Tonder		2015
Abstract It is estimated that the three coal layers in the Springbok Flats contain about 5 TCF of coal bed methane (CBM). Two sedimentary basins, namely the southern Tuinplaas basin and the northern Roedtan basin, exist with coal layers with a total thickness of 7m which occurs mainly in three mayor seams. The coal layers are located between 20 m to more than 600m. Farmers in the Flats are concerned about the environmental impact of fracking the coal beds. They are mostly worried about the risk of groundwater pollution; the drawdown of the water table and the producing of a bad quality water during the mining process. They set up an EPA for the Springbok Flats in 2010 and until now, they have stopped more than 6 companies to conducted exploration (stopped strictly on account of the different laws in SA that were not adhered too). On average, 1000 liters of water is produced for every 2000 cubic feet coal bed methane mined in the USA. The quality of the produced water is not good (with typical Na values of more than 5 000 mg/l) and cannot be used for irrigation purposes. It is thus expected that about 500 million m3 of bad quality water will be produced for every 1 TCF mined in the Flats. This groundwater will be removed from the system and it is expected that a drawdown of up to 30m will be evident at places in the Springbok Flats. There are also a large number of dykes and faults in the Flats which imply that the upward movement of methane and water will be very probable after abandonment of each coal methane well.