numerical modelling

Event Debrief:Decision support groundwater modelling - in spirit or in fact? (GWD GAU)

22 Apr 2022
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Home News Event Debrief:Decision support groundwater modelling - in spirit or in fact? (GWD GAU)

Geohydrological update and numerical modelling of the Langebaan and Elandsfontein Aquifer Systems

The Saldanha / Langebaan area is expanding at a significant rate, increasing the water demand for the area. The expansion comes from the industrial, residential and tourism sector. In addition there are economically viable deposits of silica and phosphate in the area. Ecosystem functioning in the area is also to a degree dependent on groundwater. All of these factors require an improved understanding of the geohydrology of the area. The geology of the area consists of basement Cape Granite and Malmesbury Group rocks that underlie the sediments of the Sandveld Group.

Application Of Environmental Isotope Tools To Improve Conceptual And Numerical Modeling Of Groundwater Flow In Kosh Goldfields, Witwatersrand Basin, South Africa

Environmental isotope and hydrochemical analyses were employed to improve existing understanding of groundwater flow dynamics in the defunct mine for assessing the source of water at a pumping shaft located near Stilfontein Town, Northwest Province, South Africa. Currently pumping is done using the shaft at an average rate of 37,000 m3 /day to prevent flooding of downstream mines.

Open Source Software for Hydrogeologists

There are various software packages used by hydrogeologists for a variety of purposes ranging from project management, database management, data interpretation, conceptual and numerical modelling and decision making. Software is either commercial (produced for sale) or open source (freely available to anyone and for any purpose).

The objective of this paper is to promote open source software that can be used by the hydrogeological community to reduce expenses, enhance productivity and maximise efficiency.

Rigorous Methodology For Sustainable Yield Estimation Using Groundwater Numerical Modelling Validation To Detailed Long Term Pumping Test Data

Groundwater numerical models are commonly used to determine the impact that groundwater abstraction has on the ability of surrounding areas to supply water, and thus to inform Water Use Licence (WUL) Applications. However, data available is often limited to that generated by relatively short-term geohydrological studies and pumping tests. In most cases this data and the degree of defined uncertainty in the model results are sufficient.

The Geohydrological Setting Of The Elandsfontein Phosphate Mine, West Coast

The Elandsfontein Phosphate Mine is situated midway between the Langebaan Lagoon and the town of Hopefield. It is located on the Cape West Coast, within the Saldanha Bay Municipality. The mine is positioned within the Elandsfontein Aquifer Unit – which comprises an upper and lower aquifer separated by an aquitard. The economic phosphate layer is situated within the saturated zone of the Upper Aquifer Unit. There are fresh water inflows into the Langebaan Lagoon and all measures must be taken to ensure the natural geohydrological flows are not impacted.

Alluvial Wellfield Optimisation And Management Using Numerical Flow Modelling And Seasonal River Stages

Three dimensional numerical flow modelling has become one of the best tools to optimise and management wellfields across the world. This paper presents a case study of simulating an existing wellfield in an alluvial aquifer directly recharged by a major perennial river with fluctuating head stages. The wellfield was originally commissioned in 2010 to provide a supply of water to a nearby Mine. Ten large diameter boreholes capable of abstracting ±2 000 m3 /hour were initially installed in the wellfield.

Numerical Modelling Of a Coal Mine to Improve the Understanding of Mine Water Decant: A 1000-Piece Puzzle

A coal mine in South Africa had reached decant levels after mine flooding, where suspected mine water was discharging on the ground surface. Initial investigations had indicted a low-risk of decant, but when ash-backfilling was performed in the defunct underground mine, decant occurred. Ash-backfilling was immediately suspended as it was thought to have over-pressurised the system and caused decant. Contrariwise, a number of years later decant was still occurring even though ash-backfilling had been terminated.

The Seven Deadly Sins of Numerical Modelling

Pope Gregory defined the seven deadly sins in order to guide the Catholic Church in the 6th century. The past 20 odd years in the industry has shown that there are several mistakes that are repeatedly made by numerical modelers. Although we all acknowledge that any numerical model is a non-unique solution, and that there exists and infinite number of solutions, there are several sins that will prevent the model from giving an accurate representation.