An economy and ecosystem symbiosis: barrier systems for water conservation and pollution control

Abstract

An awareness of the rate at which water resource development took place in South Africa being supply driven, until relatively recent times, leads to an appreciation of the changing philosophy in respect of water conservation and pollution control, as well as essential amendment to principles and procedures. Reconciling water demand and supply in catchments requires concurrent consideration of available water quantity and quality. This stimulates the need for change in the way we view water uses and brings about business opportunities in the sector. The review of infrastructure designs in support of water use and mining applications for industrial and mining waste has developed and transformed along with improved technology and changes in legislation since 1994 in South Africa. A containment barrier system comprises of both filter protected drains and low permeability liners which are visible in the short term until covered. They are required to perform effectively after initial use and are often inaccessible for the operating period and subsequent service life of decades or even centuries. This paper presents a regulator's perspective of commonly repeated deviation from accepted norms and standards in the engineering profession, as applied to pollution control facilities. Emphasis is placed on the standards of today with experience reflecting on the past five years of design reviews, leading to conclusions and recommendations for facility owners and practitioners. Examples of procedure, mechanisms, performance, specifications and socioeconomic benefits are addressed. It is postulated that in the near future many mining and industrial developers will choose to improve containment standards of barrier systems as a component of reengineering water demands and for economic advantage while embracing contributions from ecosystem services.

Interactions of Per- and Polyfluoralkyl Substances (PFAS) with Landfill Liners

“…For this calculation, a hydrated density of 1.9 g/cm³ was used for the GCL, equating to a hydrated pore volume of ≈ 45 cm³ in the test specimen. 2 Hydraulic conductivity tests were conducted on non-prehydrated thermally-locked, needle punched GCL samples (100 mm dia. disks).…”

“…Waste containment facilities are critical infrastructure providing essential community services. Waste containment facilities such as municipal solid and hazardous waste landfills and repositories are indispensable for mitigating the long-term environmental and human health impact of contaminants [2]. Hydraulic barrier liner systems are required to minimise the escape of pollutants into soil and groundwater from these containment facilities and to achieve the aim of long-term and safe storage.…”

Design of a lined platinum tailings storage facility in South Africa

“…The Department of Water and Sanitation (DWS) no longer condones South Africa's philosophy of the past 20 years, in terms of which dilution of water contamination and dispersion relying on attenuation was regarded as acceptable (Legge, 2019). Protection of water resources, and prevention of contamination in the first place (source) is now being sought in preference to mitigating contamination spread (pathway) and pollution cleanup (receptor).…”

“…Rolls of black geomembrane can heat up if ventilation is not allowed through stacks of the material. The upper exposed surface of a geomembrane was recorded to heat up to 83-86°C at midday at various sites in Limpopo (Legge, 2019). If covered with a thin (100 mm) layer of soil or tailings, the temperature of the geomembrane and number of associated wrinkles was found to reduce significantly.…”