More than $750 million could be spent over hundreds of years to cleanup Faro former lead-zinc mine and mitigate environmental damage before it becomes unmanageable.
At a technical briefing Wednesday, government officials explained the options for cleanup have been pared down to six for three sites.
Depending on the combination of options, the cost could be $250 to $850 million for initial cleanup, but estimated long-term costs could be between $2.7 and $4.2 million annually for hundreds of years.
“We’re looking at a project that’ll last for 500 years. We don’t have a walk-away solution and we’ll be looking at perpetual care and maintenance,” said project manager Stephen Mead.
“None of these options allow us to lock the gates and throw away the key. We’re going to be there for the long term.”
The Yukon and federal governments along with the Selkirk First Nation and Ross River Dena Council are assessing all options for reclamation.
A final recommendation should be made by early 2008 after consultation with groups and area residents, said Mead.
The federal government will review the submission for initial funding approval and then a more detailed design will go through the Yukon regulatory process.
After two or three years, final funding approval is required at the federal level. Major components of the reclamation could start in 2012.
There are nearly 60 million tonnes of potentially toxic tailings sitting at 5,000-hectare minesite, which originally opened in 1969 just north of the Faro town site.
The environmental problems pose no risk to human population, said Mead.
The water quality is relatively good for the site, but when it comes to a peak in the next 100 years, collection and treatment costs will be high, he said.
The major cleanup is meant to prevent a big contamination peak, or at least make one more manageable.
The ability to deal with contamination diminishes over time and the current care and maintenance program will be unable to handle the environmental conditions.
“That’s not over a hundred years. It’s over a much shorter timeframe,” said Mead.
Ottawa will pay the bills for the entire project under the Federal Contamination Sites Action Fund. The Yukon government is playing a managerial role.
Three different areas of the mine are due for cleanup: the Faro mine pit, the Faro tailings area, and the Vangorda/Grum area with two open pits.
Moving the tailings back into the Faro pit by mixing them with a liquid solution could cost about $420 to $520 million and will add 745 person years in employment, or about 70 jobs a year over 10 years of 35 jobs over 20 years.
It could take 10 to 15 years to actually move the tailings, then 20 years to clean up residual material.
“You’re looking at 30 to 40 years of intensive work,” said Mead.
The second option is to stabilize the tailings where they sit by upgrading dams to international standards, covering the tailings with soil and growing vegetation on top, and treating contaminated water for hundreds of years.
Maintenance of this option costs about $130 to $150 million and could create 336 person years of work over about 10 years.
The third option involves moving some tailings in the lower portion of the valley and covering other tailings with waste rock and soil at a cost of $180 to $250 million, creating 552 person years in employment.
“No matter what we do, we’ll be collecting and treating contaminated water over hundreds of years,” said Mead.
The one option at the Faro pit includes building a new channel for the North Fork Rose Creek to keep it clean and move waste rock back into pit with soil coverage.
Again, contaminated water will be collected and treated for hundreds of years. The $80 to $220 million cost, depending on the thickness of cover, could create 230 person years in employment.
At Vangorda/Grum, one option includes backfilling the Vangorda pit with waste rock with soil and lime and covering the Grum waste rock with soil while building a new channel for the Vangorda Creek over the filled pit.
This would cost an estimated $90 to $110 million, adding 226 person years in employment.
Option two suggests resloping and covering Vangorda and Grum waste rock where it sits, re-vegitating the covers, and collecting and treating contaminated water for hundreds of years. This could cost $40 to $60 million, adding 79 person years in employment.
In the interim period, work is beginning this summer to address current environmental problems at Faro, including the emergency tailings area, which is discharged into the valley and adds highly contaminated material to the creek.
“We’re in a position to be able to address some of the key elements of the site clean up in advance of waiting for the final plan,” said Mead.
“Let’s do them now instead of waiting until 2012,” said Mead.
The Faro mine closed in 1999 and when owner Anvil Range was unable to finance a closure plan after falling into bankruptcy.
The international accounting firm Deloitte Touche was selected by the company’s creditors to care for and maintain the site.