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No. 203: Review on environmental risk assessment of mining chemicals used for mineral separation in the mineral resources industry and recommendations for Greenland

Bach, L., Nørregaard, R.D., Hansen, V. & Gustavson, K. 2016. Review on environmental risk assessment of mining chemicals used for mineral separation in the mineral resources industry and recommendations for Greenland. Aarhus University, DCE – Danish Centre for Environment and Energy, 34 pp. Scientific Report from DCE – Danish Centre for Environment and Energy No. 203. http://dce2.au.dk/pub/SR203.pdf

Summary

This report provides background knowledge that allows carrying out an environmental risk assessment of mining chemicals that expectedly will be used for separation of minerals in the future in the mining resource industry in Greenland. The Greenlandic environment is as other arctic areas particularly sensitive to contaminants. Therefore, the standard tests on mining chemicals performed under temperate conditions may require some adjustment, such as use of additional sensitivity factors, when applied for environmental assessments under arctic conditions.

The general separation processes of minerals and the application of different types of chemicals are described. This is followed by a description of the regulatory framework for environmental risk assessment of chemicals in other relevant countries. The environmental risk assessment framework reviewed in this paper is based on an evaluation of the properties of the individual chemicals with focus on persistence, bioaccumulation and toxicity (PBT). Such a framework is used in the assessment methodology of European Union (EU), Australia, Canada and United States (US), and it is recommended that environmental risk assessment of mining chemicals to be used in Greenland follows the same principles.

At present, all mining chemicals and use of chemicals in the processing of minerals must be approved by the Greenlandic authorities. It is recommended that this procedure continues. Consequently, the mining companies have to submit an application in good time before the intended use of the chemical and the application must include a full description of the chemicals to be applied in the mining project, including detailed information on the composition of the products with CAS numbers. Data on toxicity, biodegradability and potential for bioaccumulation have to be provided and if such information does not exist, data on product ingredients must be made available. The application must also contain information on the proposed quantities of the chemical to be used and details on its chemical and physical properties and fate, including how the chemical will be managed and handled after its use and its concentrations and quantities in tailings, process water and drainage water. It is recommended that initial evaluation and regulation of mining chemicals in Greenland is based on principles for evaluation and regulation of chemicals in Convention for the Protection of the Marine Environment of the North East Atlantic (OSPAR) and EU.

Very little information on toxicity, degradation and bioavailability in arctic conditions is generally available. In case of uncertainties, supplementary “arctic” tests and studies must be conducted.

In the active phase of the mining and post-closure, an environmental programme must be implemented to monitor the use of chemicals and release to the environment. Effluents of mineral processing as well as drainage and seepage effluents must comply with requirements specified by the environmental regulatory authorities.

Overall, it is recommended that all activities involving use of chemical agents in mineral extraction should comply with the best available techniques (BAT) and best environmental practice (BET).