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Processing facilities at Ryan Lode closed Fairbanks Gold Mining has started reclamation, clean up of contamination at shuttered gold mine near Ester, has filed processing closure plan with state regulators Patricia Jones PNA Contributing Writer
Fairbanks Gold Mining Inc., operator of the Fort Knox Gold Mine, is going through the expense and the myriad of regulatory steps required to close process facilities at a hard rock gold mine in Alaska.
But it’s not the company’s mammoth-sized mine and mill, which produces almost 450,000 ounces of gold a year, that the company is currently closing and reclaiming.
Instead, it’s a much smaller hard rock gold mine, called Ryan Lode, a few miles west of Fairbanks near the peak of Ester Dome and smack in the middle of a residential subdivision.
So far, Fairbanks Gold, a subsidiary of Kinross Gold, has spent more than $800,000 to clean up the shuttered heap leach mine that overlooks the Parks Highway, just outside of the community of Ester. “That’s the agreement we have with DEC,” said Michelle Roller, senior environmental and educational specialist at Fairbanks Gold. “Also, doing it right is the track record we want to maintain, because we want to continue doing mining in Alaska.”
The company’s work at Ryan Lode reflects their commitment to future reclamation plans at Fort Knox, she added.
More work remains on the Ryan Lode property. Last fall, Fairbanks Gold submitted a plan to close the property’s processing components with a long-term monitoring plan to the Alaska Department of Environmental Conservation. The public comment period for the plans closed January 13. DEC should then issue a decision on the permit to close the processing facilities.
Property’s history The first recorded gold exploration and claim staking at the Ryan Lode property was in 1912-1914, when nugget-sized gold was pulled from the near-surface deposit.
In recent years miners looked for microscopic gold and Citigold Alaska Inc., developed the property as a hard rock mine, extracting gold from host rock using a heap leach method. Crushed rock mixed with cement and lime was placed on pads covered with protective liners. A cyanide solution was sprinkled over the ore, dissolving gold from the rock and causing it to leach out of the pile for final recovery.
Citigold operated the mine and leach pads for some two years, shutting down in 1989. The property was acquired by LaTeko Resources, a Vancouver-based junior exploration company.
LaTeko did exploratory drilling and attempted to generate interest in the property during the early and mid-1990s, but found no takers. The mine was included in the company’s 1999 acquisition by Kinross Gold.
Possible feedstock for Fort Knox Initially, Fort Knox managers viewed Ryan Lode as a potential source of supplemental feedstock, but plans to truck the ore for processing raised concerns from residents living near the mine site about truck traffic, mine noise and possible contamination of area water wells.
This despite the fact that the borough’s planning department had designated the area a Mineral Lands zone, a classification that “is intended to protect mineralized areas from intrusions of incompatible land uses, particularly residential uses,” according to a draft revision of the Fairbanks North Star Borough’s mining and minerals land use plan.
“Two million tons of gold ore were identified on Ester Dome. But proximity to residences and lack of water were potential challenges to the development of the gold mine,” wrote the borough plan’s authors. Some of that opposition came about because of the property’s prior history. Citigold put the property on the state’s list of contaminated sites in 1989, due to chemical and fuel spills that occurred during mining operations in the 1980s.
Additional exploratory drilling by Fairbanks Gold also didn’t prove up the property as a profitable venture, especially late in 1999 and in 2000, when gold prices bottomed out. “We had to use our limited funding more in one particular area … more feasible than to go for Ryan Lode,” Roller said. “We’re going to keep it open for additional exploration, but right now, we are focused on process component closure. The higher gold price may justify additional exploration.”
Shift to clean-up work Fairbanks Gold began cleaning up the property during its initial exploratory effort. That was part of an agreement with DEC by which the company promised to clean up the property, but did not assume liability for environmental damage left by past owners.
The company has “held up their part of the deal,” said Douglas Bauer, environmental engineer associate at DEC. “Fairbanks Gold is doing an adequate job of cleaning up the site. What they’ve found, they’ve cleaned up.”
Bauer, DEC’s project manager for the contaminated site clean up, said the environmental damage is a low priority compared to other contaminated sites in Alaska. “Based on the information we had received, it was a low ranking,” he said.
DEC was glad that Fairbanks Gold took on the task of the cleanup because prior owners only cleaned up what they had reported.
“When things were found, they were dealt with at that time,” Bauer said.
When Fairbanks Gold took over the property and completed a site assessment, additional contamination was discovered. While not liable, the new owners have the financial resources to clean up the site, unlike past owners, said DEC’s Pete McGee.
Completed clean up Contamination that Fairbanks Gold has already tackled includes remediation of diesel-soaked soil. Initially, the company dug up and hauled contaminated soil to a local firm, which employed a thermal method of remediating the soil. To eliminate transportation costs, Fairbanks Gold suggested to DEC that it could achieve similar results on site.
With DEC approval, Fairbanks Gold placed more than 1,000 cubic yards of material on a lined heap leach pad. Fertilizer was added and tilled into the material, which be tilled again this spring. Overall level of contaminants has already dropped 50 to 60 percent, Roller said.
“There were typical diesel releases from underground storage tanks that were removed,” said Bauer, at DEC. “Fairbanks Gold got as much contaminated dirt as they could. They were digging in, and started to encounter a slope stability problem. That, combined with there being no receptors for groundwater that could be contaminated — they removed as much as they practically could.”
Other contamination included crucibles used in the assaying office. Those containers containing some lead were sealed in 55-gallon drums, then buried on one of the heap leach pads. Four tons of crucibles were found and disposed of.
While that method of disposal is definitely a “no-no,” Bauer said, none of the drums had leaked.
Some lead had contaminated soil at that pad, and in July 2000, the company hauled away the last of 50 tons of lead contaminated soil.
Finally, the company has already properly closed 140 open exploratory drill holes left by past owners, Roller said.
Land reclamation started So far, the company has reclaimed exploration pads, access roads, three ponds and a laydown yard, Roller said. That includes draining water, folding in a protective liner and filling in the pond and giving the site a gentle slope. The ground was seeded in the fall and watered.
About 10 acres of the property’s process components remains to be reclaimed, including one large pond and a heap leach pad.
The company’s monitoring plan calls for a number of tests during closure and in subsequent years. In particular, surface and ground water will be monitored for up to 35 years after closure is final and the property meets the state’s water quality standards.
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