A guide to leading practice sustainable development in mining

Introduction
In a perfect world, mines only close when their mineral resources are exhausted and
a mine closure plan is in place and progressively implemented. There is time available
for planning, monitoring and trials, and funds are externally held to cover the costs
of implementing the closure plan. Pre-determined outcomes can be achieved or
progressed satisfactorily and there should be ample opportunity to overcome any
major issue that may create problems after closure. Stakeholders are prepared for
the intended closure date, employees can plan to find alternative employment, and
the community has the opportunity to work with the mine to ensure sustainable
benefits from the mining activities.
However, in the real world, mines extract reserves not resources, and the grade and
tonnage of reserves vary from day-to-day depending on the commodity price, ore
quality or grade, further exploration results, geotechnical complications and other
factors which can result in mine closure before the estimated reserve has been fully
extracted. This situation can create significant problems for the mining company, the
community and the regulator.
There are many reasons why mines may close prematurely. Research shows that
almost 70 per cent of the mines that have closed over the past 25 years in Australia
have had unexpected and unplanned closures (Laurence, 2006). That is, they have
closed for reasons other than exhaustion or depletion of reserves. These include:
economic, such as low commodity prices or high costs that may
lead a company into voluntary administration or receivership.
geological, such as an unanticipated decrease in grade or size of the ore body.
technical, such as adverse geotechnical conditions
or mechanical/equipment failure.
regulatory, due to safety or environmental breaches.
policy changes, which occur from time-to-time,
particularly when governments change.
social or community pressures, particularly from non-government organisations.
closure of downstream industry or markets.
flooding or inrush.
Poorly closed and derelict (orphaned and abandoned) mines provide a difficult legacy
issue for governments, communities and minerals companies and, ultimately, tarnish
the mining industry as a whole. Increasingly, as access to resources becomes tied
to industry and corporate reputation, effective closure processes and satisfactory
mine completion becomes critical to a company’s ability to develop new projects.
Poor planning and inadequate financing commonly increase the costs of closure and
decrease overall profitability, hampering a company’s ability to develop new projects.
Taking a more integrated approach to mine closure planning, and doing it earlier, can
achieve effective mine closure and completion, and ameliorate the negative effects
of unexpected or unplanned closures.
132 LEADING PRACTICE SUSTAINABLE DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY