One of the most vexing problems that mining companies face has nothing to do with mining.
It's what happens to the mine after the minerals have been depleted, the mine is no longer economic, and it's time to shut the operation down. In Australia, historically when mines close rarely are the mining leases relinquished. More commonly, the lease is retained and the mining company puts the mine on care and maintenance, waiting for mineral prices to go up or other factors that could bring the operation back to life. All too often the minesite ends up falling into an “abandoned” status.
In order to regulate this practice, the various State Governments have implemented requirements for current and future mines in Australia. The regulations are different for each State; in Western Australia for example, a mine closure plan is required to develop the mine and it must be updated every three years.
Peter Waters, Mining Sector Lead, Asia Pacific with Stantec Australia, said up until recently, decisions about mine closure in Australia have tended to have little consideration of how the land might be used after mining. However, this is beginning to change, especially as non-governmental organizations begin to demand action on abandoned and orphaned mines.
“What we're now seeing is that the more progressive proponents in Australia are saying we need to look at a walk-away solution. [The mining companies] understand that they won't be mining here forever and, in fact, they don't want to have any environmental legacy,” says Waters. “Their preference is often to ultimately relinquish the land they have and give it back to the state so that whoever wants to use it next can do so. As a result, in Australia, there is now much more of a focus on having a vision.”
Having a vision for mine closure is something that Stantec, a global consulting firm, has taken to heart through a software tool it calls PRAC™.
Progressive Rehabilitation and Closure was developed to provide mining companies with an easy, efficient and organized process for progressive rehabilitation and closure of a mine. One key benefit of the tool is that it captures all closure-related data in one location. In over 20 years’ experience of working with mining companies to plan and execute closure, Stantec has found clients often have all the information needed, but it is stored by different departments and libraries, and sometimes knowledge crucial to closure activities has been lost. PRAC™ is a tool that helps companies manage closure-related information, and to provide a more efficient means to implement closure tasks developed through the mine closure planning and implementation process.
All information is accessed through a graphical interface that can store any type of data, information or report. Data can be categorized in many different ways, enhancing the way data can be archived and searched. It includes closure task planning and management – Gantt charts and email alerts. Tasks can be accessed and updated remotely or in the field. Dashboard reporting is designed to generate monthly or annual reports tailored to a client’s specific requirements.
By undertaking closure progressively during operations, the liability of the operation at closure is reduced. PRAC™ tracks liability reduction. Mining companies save resources and costs by having all of closure tools and data in one place.
“PRAC™ allows you to zoom in on different land forms and different features and it will actually outline what needs to happen in each of those features and by when. It has hyperlinks for the various reports that are associated with that land form. So it's a very quick and easy way for the site people to navigate through different plans and see what's required in the different land forms at different times. It also acts as a library, for the data,” says Waters.
He said the PRAC™ tool was an integral part of Stantec’s closure and rehabilitation work at the St. Ives mine in Western Australia. The underground and open-pit gold mine has been operating since the 1960s and the operators of the mine were looking for opportunities to commence closure activities whilst still in operations.
Stantec completed an 18-month closure planning study, culminating in 11 technical studies that formed the mine closure plan. Apart from these technical studies, the consultancy sourced and catalogued all closure related documentation collected during the history of mining on the site. Several hundred documents were collated as part of the study, which provided a rich data source to support the technical studies. All this data is now located electronically in one centralised location through PRAC™.
Along with having detailed knowledge of all aspects of an operation, Stantec advises mining companies to begin their closure process early. By planning early, costs can be spread out over the life of the mine rather than deferred to the end of life when the mine is seeing depleted resources and revenues at the same time as closure costs are ramping up. This provides an opportunity for mine stakeholders to be consulted and give input about how closure may affect them – reducing the chance of conflicts and raising the opportunities for a land-use plan that satisfies all stakeholders.
Content was originally published on Mining.com.
About the Author
Peter Waters is an experienced mining professional based in Western Australia. With qualifications in geology and environmental management, he has worked in a variety of technical, supervisory and leadership roles across the mining cycle from greenfields exploration to post-mine closure.More Content by Peter Waters