A guide to leading practice sustainable development in mining

Risk Management
Risk at closure and post closure (legacy)
Risks associated with closure and post-closure phases in the mine life cycle cover
both economic and non-economic consequence types. These risks are long term
in nature. The expectations of the local community, government, landowners,
neighbouring property owners and non-government organisations (NGOs) need to
be taken into account. A well-planned and managed closure process will protect the
community from unintended consequences well after the mining company has left
the district and will protect the reputation of the company.
Closure strategies for some mine operations may include initiatives to create
enduring legacies that enhance social and/or environmental values in the vicinity
of the mine and surrounding communities. In this way, the reputation of the mining
company will be enhanced.
Australia hosts examples of the long term risks of older mines where closure wasn’t
considered until relatively recent times. The Mount Lyell Mining and Railway
Company Ltd copper mine in Queenstown, Tasmania, resulted in more than 100
million cubic metres of mine tailings, smelter slag and topsoil being deposited into
the King River and Macquarie Harbour in its 100 years of operations. Despite the
cessation of tailings dumping, exposed tailings on the river banks and in the delta
continually leach iron, manganese, aluminium and copper, which have contributed
substantially to the metal loads in Macquarie Harbour waters and sediments. The
case study in the Leading Practice Risk Handbook (p.17) illustrates the outcomes of
using risk assessment techniques in providing guidance in the mine rehabilitation
and closure process.
Figure 5.32 - The King River in SW Tasmania (Image Source: Mount Lyell Mining)
A GUIDE TO LEADING PRACTICE SUSTAINABLE DEVELOPMENT IN MINING 169