Australian miner Oceana Gold has come in for high praise from the Department of Conservation for its restoration work at the former Globe Progress goldmine near Reefton.
The former open case mine pit is becoming a lake, and surrounding material contoured and planted with thousands of native trees. Photo: LDR / Lois Williams
Oceana ceased mining in 2016 after extracting 610,000 ounces of gold from the 260ha historic site in Victoria Forest Park, and is now about halfway through the rehabilitation project.
DOC Western South Island operations director Mark Davies, of Hokitika, told a recent meeting of the Inangahua Community Board that the company's plans to restore the site had been "world class" and it had followed through on its commitments.
"Oceana Gold has delivered 100 percent on their thinking and planning to date. This is public conservation land: we needed a world-class standard of restoration and so far we've got it," Davies said.
DOC was holding a bond paid by Oceana when it gained consent to mine the site in 2004, and was reimbursing the mining company as certain milestones were met.
Reefton visitors were given tours of the old Globe mine site by the company as part of the town's 150th celebrations last October. Photo: LDR / Lois Williams
A fly-over video screened for the board showed the two main pits are now lakes surrounded by re-contoured and replanted hills.
Run-off from the slopes was being treated by a system developed at Cardiff University, the company reported.
The water was oxygenated before flowing into two filter-ponds, causing the iron to come out of the solution and bind with arsenic particles before settling on the gravel bottom.
One pond at a time could be drained, the material dug up and safely stored and in time the minerals entering the ponds from the waste rock would be exhausted.
The water now running into Devils Creek, a tributary of the Inangahua River, was of good quality, the board heard.
"More than 130 hectares have been completely rehabilitated, including the planting of approximately 800,000 native seedlings."
Birdlife had increased around the lake margins, the company reported.
"We'll be planting an extra 64,000 wetland plants around the margins this year and another 200,000 beech and manuka seedlings by December 2023."
Wetland areas are being created and planted to attract birdlife. Photo: LDR / Lois Williams
Community board chairman John Bougen said it was encouraging to hear that Oceana was meeting its obligations and suggested some of the historic mining gear found at the site could be preserved at the old School of Mines in Reefton.
Davies said that was one of many options the Reefton community would be able to consider as Oceana packed up.
"There are a number of ideas floating around the community; it's been suggested we keep the access road and bridge, maybe set up a mountainbike park. All of these things we can entertain once the site is handed back to us, if the council is interested."
Oceana plans to dismantle and remove its buildings and plant from the Globe site this year, with some of it going to its Waihi goldmine in Coromandel.
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