Advancing Together With Barrick Gold

Environment A look back at the Misima mine closure

Long-term planning led to successful closure of Papua New Guinea mine

A flight over Misima Island today reveals two lakes nestled between a vast landscape of native plants and trees.

What many visitors can’t spot from above, or even on parts of the ground of this small island about 200 kilometers east of the Papua New Guinea (PNG) mainland, is evidence of a once-operating gold mine.

The Misima mine was a joint venture between Placer Dome (80%) and state-owned Orogen Minerals (20%) that produced 3.7 million ounces of gold from 1990 until the mine closed in 2004. The lush terrain left behind is the result of years of reclamation planning that dates back to 2000, long before shovels stopped scooping ore from the ground.

When Barrick took over Placer Dome in 2006 it also took charge of the Misima sustainability plan.

“This was the first mine closure in PNG and there was no defined process,” says Ila Temu, Barrick’s PNG Country Manager. “We had to define the process and the framework, working closely with the government. Then we had to demonstrate that the agreed closure criteria were met before relinquishment was granted in April 2012.”

The 12 square kilometers of land, half of which was disturbed by mining, was returned to the Misiman people for their long-term use. Today, the land is used for food production and other uses, such as house-building for the roughly 5,000 Misiman people who live on the island. The relinquishment was possible because the mine closure was planned early and handled properly, says Walter Benko, a Reclamation and Closure Superintendent at Barrick’s Australia-Pacific regional business unit.

“Planning for closure with objectives and targets is crucial,” says Benko, who was directly involved in the Misima reclamation and relinquishment. “Barrick’s closure standard is good and detailed. Its focus is mine closure planning done properly.”

The key to success was ongoing stakeholder consultation, which Benko says involved a number of groups and strategies. For example, the Misima Mines Closure Committee was formed, which included Barrick, landowners, regulators and government representatives. The committee’s goal was to implement the sustainability plan to ensure environmental, social and economic impacts from the mine’s closure were addressed at each stage of the process. That included everything from rehabilitating the land and ensuring clean water, to helping local people find job opportunities now that the mine is closed and the reclamation work has ended.

Barrick offered regular tours of the old mine site to show the local community the results of the revegetation as it was developing. The company also relied on advice and feedback from its employees, 90 percent of whom were from the local community. There were also numerous meetings and reporting to regulatory bodies, Benko says.

Finally, the relinquishment was possible due to a decade of monitoring the reclamation activity that began with Placer and continued with Barrick, Benko says.

A great deal of that monitoring involved managing water quality. A baseline for comparison was established by measuring the presence of sediment and metals in water from the northern, undisturbed side of the island and comparing it to the southern part, where the Misima site was located.

“If we could produce a similar water quality level in our impact zone on the south coast, we must not be doing a worse job than nature,” says Benko, speaking to the rigors of the monitoring process. “A lot of the process was about using common sense and having everyone work together to do the right things.”

Misima timeline:

  • 1988 - Misima Mine construction commenced
  • 1989 - Official opening by PM Rabbie Namaliu
  • 1992 - Production reached 1 million ounces of gold
  • 1995 - Production reached 2 million ounces of gold
  • 2001 - Mining from open-pits ceased
  • 2004 - Milling of ore ceased
  • 2005 - Deconstruction completed
  • 2012 - Relinquishment achieved (April)