DEADWOOD — A group proposing gold mining activity near the rim of Spearfish Canyon has refiled a Conditional Use Permit (CUP) Extractive Industry Application with Lawrence County.
Thursday, a group of around 15 individuals, including members of the Lawrence County Planning and Zoning Commission, caravanned to the remote proposed mining site of the Deadwood Standard Project.
The name of the partnership proposing mining is Valentine Mining Company, LLC (VMC).
“It’s pretty clear what we want to do up here. We want to mine up here,” said Dana Bender, the project’s permitting manager, who is from Rapid City.
First proposed 2012, the partnership includes a half dozen South Dakota residents.
The company has acquired a state large-scale mining permit but needs county approval to begin mining.
The company’s state permit authorizes mining 870,000 tons of gold ore from 14 small surface quarries ranging in size from one-half acre to 5.2 acres.
The permit authorizes ancillary activities such as topsoil stockpiling, overburden stockpiling, crushing, and ore hauling. The permit requires the processing of ore to be conducted off the site.
In 2012, the company requested a CUP from Lawrence County for a significantly larger proposal for the Deadwood Standard Project, which included onsite mineral processing.
Company officials ultimately decided that onsite mineral processing is not practical, and processing will not be conducted onsite.
“What’s a little different about this is, in 2012, we did approach the Deadwood Standard Project with a bigger permit boundary. It was a way bigger project. It was 80% larger than this project,” Bender said.
Overall, he said, 14 pits would be excavated over the life of the mine, affecting a total area of 31 acres.
The CUP originally made it through Lawrence County planning and zoning in 2012 and was considered by the county commission, which told the applicants to come back when their state mine permit was obtained.
The biggest issue at the time of the last permit request was the inclusion of an on-site enclosed vat leach mineral processing facility, which has since been scrapped, as mining principals proposed a plan to haul the ore out of the mine to be processed off-site.
Mark Nelson, of VMC said there have been 900 drill holes made on the property.
“This property has been mined intermittently since the late 1800s,” Nelson said. “Like many of the gold operations in the Black Hills, it worked for a while in the late 1800s, early 1900s and then became active again in the early ‘30s, when the price of gold went up to $35 per ounce. … extensive exploration was done here in the 80s and the 90s.”
Nelson said the proposed mine would consist of several small, shallow pits and overburden stockpile.
“The ore here is very shallow. Here the ore is about 20 feet below us and it is a unit that is about 10-15 feet thick,” Nelson said. “It is a number of very shallow quarries. The overburden that would have to be excavated to reach the ore would have to be put in these temporary overburden stockpiles.”
Nelson said that in general, a couple of the small pits would be mined and backfilled with the overburden when completed.
An attendee asked what the maximum pit depth would be.
Nelson said the average depth is 23 feet.
“The ore is shallowest on the west,” Nelson said. “By only having a few of these open at any give time, we think that the disturbance would average about 10 acres … this proposal is about 100 times smaller than the Wharf operation, in terms of the acreage that would be disturbed at any one time.”
Nelson said that options being considered include the construction of a mill on an offsite facility that would be outside of the Spearfish Canyon watershed.
“That would be a small-scale mill, a couple of hundred tons per day,” Nelson said, adding that VMC would like to strike a deal with Wharf and would not move forward with constructing its own mill unless they have county approval of the CUP.
Nelson said that because the noise factor was a significant concern during the last application process in 2012, VMC had a professional conduct a sound study, the results of which found that the primary noise in the Canyon today is traffic.
“We tested some loud equipment. We tested some back-up alarms. We also did three test spots to see if the blasting was audible in the canyon and the results of that testing showed that none of those sources of noise were audible in the canyon,” Nelson said.
The trucks would be 15-ton dump trucks, not the 150-ton trucks that Wharf runs.
Nelson estimated there would be 10-11 truckloads of ore per day coming out of the mine to the mill.
Nelson addressed a question regarding acid rock drainage potential.
“On this property, this rock has zero potential to generate acid,” he said, later adding, “one of the primary reasons we were looking at this site was because the ore has such a tremendous acid neutralization potential.”
Nelson emphasized that what VMC is asking the county to authorize is specifically what the state has authorized in large scale mine permit 416.
“We think it makes sense environmentally. It’s a smaller scale operation. There’s no onsite mineral processing. We would use existing roads,” he said.
An attendee asked what the time frame is for mining, that is, how long from county approval would mining activity begin.
Nelson said mining consists of exploration, development, production, and reclamation phases.
“We anticipate initiating that development phase … within 12 months of the approval of the CUP,” he said. “There would be no mining in earnest here. No construction of pits, with exception of a small pit to do, say, a metallurgical bulk sample, until the mineral processing facility has been identified and that will also require permitting with the state. We would be in the development phase, likely for a period of a couple of years prior to the initiation of active mining, actual operations phase.”
A public hearing on the most recent conditional use permit proposed by the company is slated for Sept. 3.
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