Erik Skindrud | The Gazette Old mine shafts and tunnels are scattered across the county. While not currently worked, most are claimed by parties, including mining companies that are exploring plans to resume activity and recover gold. A new Gold Rush spawned by record prices for the metal threatens to pollute the Yosemite region with toxic chemicals and other impacts, an environmental group said last week.

The group Environment California wants the U.S. Deptartment of the Interior to impose a mining exclusion zone around the Park. In June, U.S. Interior Secretary Ken Salazar announced the closure of 1 million acres around the Grand Canyon in response to an upswing in mining claims and activity, the group noted.

Over the past five years, mining companies have filed 285 claims within 10 miles of Yosemite National Park, Mac Farrell of Environment California said.

A review of public records by the MARIPOSA GAZETTE reveals more than 470 active mining claims in Mariposa County. Most are held by individuals. Several companies have filed recent claims, however, including Tonogold Resources, Inc. of La Jolla, Colorado Quartz Gold, Diltz Mine Ltd. and more than 115 claims held by Troy Mining Corporation.

Mariposa County’s Mockingbird and Colorado Quartz mines operate today but they primarily produce “specimen gold”—gold that is valued for its crystalline beauty and is purchased by collectors at rates above the market price for gold.

But untold riches remain under the Mother Lode, said Jeff Janda, president of the industrial mining company Tonogold.

“It’s a crying shame,” he said. “You have one of the most important gold-producing districts in the world, and it’s not being put to use. It’s not even close to being mined out. Using new exploration technologies, new deposits can be found there.”

Environment California’s Farrell said Yosemite needs to be protected from “the boom and bust” cycle of the gold mining industry.

A new gold rush would subject the area “to chemical pollution, noise pollution, scarred land and the construction of mining roads,” Farrell said.

“There must be a buffer zone around Yosemite,” he said.

In 2010, Tonogold filed eight claims on land formerly worked as the Banderita Mine. The site is located about 10 miles east of Hornitos on the North

Fork of the Merced River.

Tonogold plans to drill test holes and recover samples to determine if the site is worth developing commercially.

If results are promising, the company would begin an environmental review process that could ultimately lead to permits that would allow it to mine ore and recover gold.

Mining activity should not be equated with pollution, Janda said. The geology of Mariposa County and the Mother Lode is suitable for limited mining that is not likely to wreck havoc on the landscape, he said.

“Nobody wants to do an open pit-style operation in that area,” Janda said.

If it happens at all, “it’s going to be small, underground operations with self-contained milling, milling that’s in a closed system where it can’t leach

(toxic chemicals) into the environment,” he said.

History shows that where gold mining takes place, “cyanide and other toxic chemicals” run off into adjacent rivers and streams, Environment California’s Farrell countered.

“A tiny amount of cyanide can kill fish and other wildlife,” Farrell said. “Yosemite is the pride of California. We don’t want to take chances here.”

Longtime hardrock miner and county resident

Bud Munch questioned the likelihood that mining would result in cyanide contamination.

“That’s not very reasonable,” he said. “There is practically no cyanide used today in mining operations in California, except very few in the southern deserts.”

A mining-related cyanide incident did occur several decades ago at Mariposa County’s Mt. Gaines Mine, Munch recalled. But it was long ago contained (and did not involve the current owner), he added.

“They cyanided the tailings from the old gold mine there,” Munch said. “It caused a little problem.”

Tonogold’s Janda said the company’s mining operation could utilize cyanide, but only in “a closed system.”

Any mining operation would go forward only after years of environmental review. The public would be informed of any application—and would have ample opportunity to comment, Janda said.

Mining companies are taking a wait-and-see approach at this point. They know there’s gold in the hills—the real question is how local folks will respond to any organized effort to resume commercial production.

Mariposa County does not currently have operations producing gold in industrial quantities, said Don Drysdale of the California Department of Conservation.

In 2009, the last year for which data is available, 20 mines reported producing significant amounts of gold. The state’s total production in 2009 was close to 186,000 ounces.

More than 143,000 ounces of that total came from the Mesquite Mine in Imperial County (in the southeast corner of the state).

A good underground miner can make upwards of $100,000 a year, Tonogold’s Janda said.

“The question now is whether the community is open to allowing mining,” Janda said. “The community may decide that mining is something from the past, and that today’s economy should rely on tourists. We’re waiting to see what they decide.

“If we’re going to get sued, or face an impractical permitting process, we’ll go back to Nevada and Alaska and work there.”