To satisfy the requirements of the Ghanaian government and recover its bond, Golden Star Resources, the operator of the Wassa Mine, planted trees where mining operations had been completed. To satisfy their needs, the surrounding residents cut down those trees and planted corn before the bond could be recovered.
Mark Thorpe, vice-president of sustainability at Golden Star, explained that the company has since adapted its reclamation efforts, engaged the local residents and found a more practicable solution that addresses the socio-economic and environmental aspects that modern mining operations contend with as a part of the mine closure and reclamation process.
The lessons learned by Golden Star were some of many that were shared at the International Conference on Mine Closure held in Lake Louise, Alberta, in September. This was the sixth edition of the conference, but the first time that it was hosted in the Northern Hemisphere. The change of venue was warranted: the 600 spaces for delegates were claimed weeks before the event. The attendees came from around the world and included a delegation of government officials from Papua New Guinea looking to integrate best practices into development of its closure regulations.
In his opening remarks, Les Sawatsky, a principal at Golder Associates and the conference chair, laid out the daunting challenge facing the industry, which has a much longer history of opening mines than closing them effectively. “What gives us the right to expect future generations to maintain thousands of closed mines that are vulnerable to failure with catastrophic consequences? To me, it is inconceivable that any provision to protect vulnerable closed mines with a plan for perpetual maintenance will be heeded or remembered after a thousand years, or even a hundred years.”
Beyond the moral imperative, Bruce Kelley, global practice leader for environment at Rio Tinto, presented a compelling business case for early and comprehensive mine closure planning. The multinational miner, he explained, has closure liabilities in the billions of dollars. The social licence of each new mine site is tied to the effective closure of other sites, and with a geographical footprint of 40,000 square kilometres, the company cannot escape notice. “Closure,” said Kelley, “is a core business function.”
Andrew Robertson, president of Robertson GeoConsulants, pointed out that mines are only growing larger, which means the disturbance of more land, the creation of more waste and the construction of higher tailings dams – all of which increase the level of risk. With this sobering introduction, Robertson outlined a top 10 list of problems associated with the practice of mine closure, where, he said “there have been more ‘oops’ moments than ‘eureka!’ moments.” The perpetual forces of nature and unforeseen catastrophic events have their places on the list, but the majority of shortcomings are related to inadequate planning, underfunding and undue “optimism for the effectiveness of new, novel and sensitive technology.”
What constitutes successful closure continues to evolve. Technical sessions focused on the nuts and bolts of reclamation such as soils and pit lakes, but there was also a discussion of the aesthetic aspect of reclaimed land and a strong emphasis on addressing the socio-economic impact of closure on the communities around the mine. Golden Star, confronted with its closure dilemma, ultimately created a palm oil plantation that has created a source of revenue for the local residents and satisfied its reclamation requirements.
Following the conference, Gord McKenna, a geotechnical engineer with BGC Engineering and a presenter, reiterated the growing attention to community engagement across the industry. “My sense is that the greatest recent revolution is in the social aspects of mining and mine closure and the need to work closely and continually with local communities,” he said. “True collaboration and shared decision-making was a new theme this year.”
“I was pleasantly surprised,” said Sawatsky after the event, “to hear a number of plenary speakers caution the delegates to avoid being too optimistic in predicting performance of their mine closure plan, and to plan for the occurrence of extreme events that will certainly occur sometime in the future, albeit infrequently. Closed mines should be designed to function with minimal negative environmental impact, forever. Forever is a very long time.”