Environmental impact of mine top-of-mind

Environmental management company Cabanga Concepts has been contracted to yearly audit the environmental compliance of uranium and gold mining company Oakbay Resources & Energy subsidiary Shiva Uranium’s operations, in Hartbeesfontein, in the North West.

The Shiva mine is operating three underground shafts that have gold- and uranium-bearing properties, with two additional underground shafts to be developed in the near future. The metals are extracted through reverse-pressure leaching technologies that provide a pure quality of metals.

“Cabanga Concepts uses modern technologies and professional consultants to model pollution plumes, water balances and salt balances,” says Shiva chief occupational hygienist David Fleet.

Further, Shiva is trying to reduce its effect on the environment by monitoring groundwater, wastewater and surface water resources in accordance with the water-use licence (WUL) requirements, the results of which are regularly submitted to the Department of Water and Sanitation.

Shiva also uses industry recognised methods for measuring and monitoring dust fall and water analysis using accredited institutions.

“Currently, Shiva is using less water than its WUL stipulates. We have discontinued the use of Klerksdorp-based water service provider Midvaal Water and now use underground fissure water in our processes. We are also drawing domestic water from boreholes to reduce our water use,” Fleet elaborates.

The mine is also involved in environmental rehabilitation projects. Shiva assesses its rehabilitation and radiation requirements yearly and, as required, has provided for mine closure rehabilitation as stipulated by the National Environmental Management Act.

“When Shiva started its openpit gold mining operation in 2010, a decision was made to continuously plan and coordinate all rehabilitation inputs in tandem with the production processes. All material is, therefore, placed and/or transported as effectively as possible to tie in to the final rehabilitation process of the terrain.”

Large areas that, among others, consist of deep openpits, have been rehabilitated and are being covered with natural grass, leaving no signs of the damage that mining caused in these areas.

Rehabilitating openpit and other surface areas is a practice that will continue.

One of the company’s tailings dams is also being rehabilitated and involves processing the tailings through Shiva’s gold plant. Over time, this process will result in a large and previously mined terrain being developed into a natural grass covered area, the company notes.

“Shiva has also developed a crushing plant, where waste rock from a large surface rock dump is being crushed into various sizes and sold as aggregate for commercial use in construction,” Fleet says.