A proposed expansion of the Dilokong mine's tailings dam, as part of increasing production for chrome producer ASA Metals, is undergoing rigorous environmental-impact assessment (EIA) before operations can proceed. The mine is located in Limpopo province.

ASA Metals commissioned consulting engineering and environmental services company Golder Associates Africa to conduct the EIA. Golder is currently completing the final phase of the EIA report, set to amend the mine's existing environmental management programme (EMP).

The EMP amendment contains the outcome of the EIA and identifies potential adverse effects of the mining operation on the environment and measures to mitigate these effects.

Ultimately, the Department of Minerals and Energy (DME) will decide, once the findings of the final EMP amendment have been studied, whether the proposed expansion of the Dilokong chrome mine's tailings dam may proceed or not and under what conditions.

Mining Motivation

In 2007, ASA Metals stated that its goal was to expand its operations by increasing ferrochrome production capacity from 120 000 t/y to 380 000 t/y. This was reported to entail the construction of two 66-MVA closed furnaces, a pelletising plant and a chrome ore beneficiation plant, for which Golder completed an EIA, at the end of last year.

However, the company has had to reduce its production rate and capital expenditure, owing to the global economic crisis and the decrease in commodity prices.

This has delayed the construction of the beneficiation plant, which in turn has negatively affected the operation of the furnaces. Furnace operation requires ore input from the beneficiation plant.

However, ASA aims to solve this problem by recovering chrome from the tailings dam at its Dilokong chrome mine. ASA conducted full production scale tests on recovering the chromite in the tailings dam to determine production viability. The tests were successful and yielded significant quantities of chromite concentrate suitable for agglomeration.

The recovered chrome will be used as part of the raw material used in the pelletising and sintering plants.

Recovery will be achieved by using a mobile tailings processing plant capable of treating 60 000 t/m.

ASA therefore, proposes to expand the footprint of the current tailings facility which will accommodate the remined tailings.

An EMP report was drawn up for the mine under previous legislation and approved by the DME in 1998.

However, in order for ASA to proceed with its proposed endeavours, an EIA is required to compile an amended EMP report.

The DME will ensure adherence to Regulation 386 of the National Environmental Management Act of 1998, which states: "The expansion of, or changes to, existing facilities for any process or activity, which requires an amendment of an existing permit or licence in terms of legislation governing the release of emissions, pollution and effluent."

The EIA will also comply with the requirements of the Mineral and Petroleum Resources Development Act of 2002, which applies to all prospecting and mining operations. The 1998 Act's principles serve as guidelines for interpreting and implementing the requirements of the overarching 2002 Act.

What The EIA Contains

Golder's EIA or EMP amendment report includes: an overview of the current and proposed activities at the Dilokong chrome mine; an overview of the existing environment in the project area; an overview of the EIA process, including a public participation process; an assessment of the potential environmental impacts associated with the proposed project; a consolidated EMP to address significant environmental issues; and a list of the affected parties participating in the EIA process.

The EIA process consists of two phases. The first phase is the scoping phase. This phase has already been completed and entailed identifying central environmental concerns, enabling Golder to focus the EIA on crucial issues. It was available for the public to comment on in December 2008 and January 2009.

Secondly, an impact assessment phase entailed the detailed study of potential effects on the environment. It is currently available for the affected community to comment.

Currently, Golder is finishing the environmental impact report and these findings will be consolidated and used to determine whether the project can proceed.

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