Monday, July 02, 2018

Sinkholes, Poison Gas, Dynamite: Inside Abandoned Mines

A century-old gold mine is a curious place, and that's a problem for those whose job it is to find bats and blasting caps as worrisome as the public finds them to be wondrous. When the 2015 fire in Owyhee County finally burned out, a team of experts from the Bureau of Land Management followed closely behind the wildland firefighters assessing the safety of public land known as the Owyhee Front. The Soda Fire burned 280,000 acres in southwest Idaho and eastern Oregon. The blaze damaged 28 mi. of roads and 150 mi. of recreation trails, severely diminishing grazing acreage in Owyhee County and requiring the rescue of 283 wild horses. But what concerned this BLM team were the abandoned gold mines that lay beneath the surface of the public land in the Owyhee Front — hazards exposed by the fire. Abandoned mines are any mining sites that were vacated before Jan. 1, 1981, when BLM's surface management regulations took effect. Those abandoned mines, and thousands more spread across Idaho, are an ongoing risk and expense for both Idaho and the federal government. Experts from the Bureau of Land Management, the Forest Service and the Idaho Department of Lands must balance limited funding, resource extraction, public safety and the unique problems that come from cleaning up messes dating back to the era of the Civil War. Gold mining of ore deposits in sand and gravel began in Silver City in 1863, and lode mining began in 1865 at the Morning Star mine in Silver City. On BLM land alone, the Idaho abandoned mine lands staff have identified and inventoried 1,480 abandoned mine sites in Idaho and 8,224 mine features — which could be anything from a 200-ft.-deep mine shaft to an old building — on those sites. There are about 210 known mines on state land, more on Forest Service land and unknown numbers on privately held land across Idaho. The Idaho Geological Survey database has mapped 9,000 active, abandoned and prospect mine sites in Idaho but estimate that there may be 8,000 more not yet included in the database. So far, abandoned mines staff have repaired 923 abandoned mines across Idaho. Phil Barbarick, the Idaho abandoned mine lands team lead, said 824 of those were physical safety hazards and 99 were environmental hazards. “We think there's probably double that out there,” Barbarick said...MORE

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