Heap-leach miners set to pull gold from Utah’s West Desert
By Brian Maffly
The Salt Lake TribuneFirst published Jan 14 2014 01:01AM
The Bureau of Land Management has approved Utah’s only cyanide heap-leach mine, but not without strong objections from Goshute officials who say the review process ignored tribal interests in wildlife, groundwater and cultural resources.
Over its nine-year life, the Kiewit Mine is expected to process 2.3 million tons of silver- and gold-bearing ore in the historic Gold Hill Mining District in the remote southwestern corner of Tooele County. For leaching, ore is piled high and doused with a cyanide solution that draws out precious metals.
A decision released Jan. 8 said potential impacts from the 104.5-acre surface mine and leach operation, located on a mix of federal, state and private land, "are considered minor and all deemed acceptable with mitigation."
But the Confederated Tribes of the Goshute Reservation contends the BLM environmental assessment is "severely deficient."
"For starters, the BLM greatly diminishes the importance of the region to the tribes," Chairman Ed Naranjo wrote in his comments. "Resting on the northern edge of the Deep Creek Mountains, the project area is right in the heart of Goshute’s ancestral homelands and encompasses an area that remains important for our tribal members either directly or indirectly."
Of particular concern are "impacts to elk and other big game that the tribes rely on for economic activity associated with guided hunting," said Monte Sanford, the tribe’s environmental adviser.
Tribal officials also insist a cultural assessment should have been conducted on the affected land.
"BLM didn’t do their duty to consult with the tribes properly," Sanford said. "They have a trust obligation to the tribes to protect sacred sites and tribal uses of the land."
The BLM made some changes to its assessment to reflect the chairman’s concerns. A message left with project manager Steve Allen was not returned.
Returning to Gold Hill • The Goshutes’ 112,870-acre reservation lies to the west of the Deep Creek Range in Juab and Tooele counties, and in Nevada’s White Pine County. The Kiewit mine is about 10 miles to the northeast of the tribal headquarters in Ibapah.
"We look forward to a cooperative relationship with all our neighbors out there, and we will make sure there are no negative impacts," mine proponent Rick Havenstrite said. "We have been there for five years. We want to make sure we are not a thorn in their side."
Havenstrite’s company, Desert Hawk Gold Corp., controls 338 mining claims and three state mineral leases, covering a total of 33 square miles in the Clifton-Gold Hill district, according to financial disclosures to investors. Some of Desert Hawk’s interest in the area stems from a partnership with Utah-based Clifton Mining Co., which owns the Kiewit claims and will reap a share of the mine’s revenue.
Kiewit, which Desert Hawk expects will yield up to 20,000 ounces of gold a year, is the only site it is developing in Gold Hill.
This district was once a busy place, with 50 mines active in the second half of the 19th century. Surface deposits of silver and lead were extracted initially. Tungsten and arsenic later were mined. Desert Hawk intends to mine up to 5,000 tons of ore a day by blasting, drilling and digging a 16-acre pit to a depth of 160 feet. Mining operations will take place 200 days a year for at least the first two years.
The operator will crush the ore and pile it onto a leach pad up to 100 feet high, then sprinkle it with 100,000 gallons a day of a high-pH sodium cyanide solution. The solution filters through the crushed ore, binding with the precious metals. The liquid is collected from the pad liner and stripped of dissolved metals, according to state permitting documents.
The leaching strategy • In the 1970s, cyanide extraction emerged as a way to profitably pull gold from low-grade ore, often at old mine sites. But it has a checkered history in Montana and other states because it uses toxic chemicals that have contaminated the ground. The process, now highly regulated, is commonly used in Nevada, which accounts for nearly 80 percent of the nation’s gold production.
Utah has seen a few heap-leach operations in the past, but none is currently active, according to Jim Springer of the Division of Oil, Gas and Mining.
Desert Hawk has obtained all of its state approvals for the Kiewit Mine, but Springer said it has yet to post the bond required under its mining permit.
Havenstrite wants to begin construction on the 20-acre leach pad as early as March and start producing gold and silver by the end of summer. After Kiewit’s production life, expected to last six years, Desert Hawk will spend three years reclaiming the area. But it won’t return the ore to the mine pit.
"We reclaim the heap and turn it into a man-made hill," Havenstrite said. The idea is to contour the tailings, cover it with stockpiled top soil and plant it with vegetation.
The Goshutes weren’t the only stakeholders to raise concerns. The U.S. Fish and Wildlife Service worried about impacts to nesting habitat for migratory birds and asked for seasonal blasting restrictions.
In response to concerns raised by the U.S. Air Force, Desert Hawk agreed to numerous new conditions because the mine is located under restricted airspace associated with the Utah Test and Training Range. No one may be present at the property on the six occasions a year that the range flies cruise missiles.
Structures and ore piles also must remain under 99 feet in height to avoid interfering with low-flying aircraft. The mine must also give the Air Force access across the project to retrieve any fallen aircraft.
But Goshute officials argued the BLM and mine operators should heed their concerns as well.
"Mining companies and the federal government have been benefiting from valuable mineral extraction at the Gold Hill area for over 150 years, extracting and exporting millions of tons of valuable minerals on lands that our tribe never ceded to the federal government nor to any other entity," wrote Ed Naranjo, the tribal chairman.