More mine collapses due for the West

Americanrivercanyon blogs extensively about the Utah mine disaster today. He names the names of the six lost miners and their three dead rescuers. He also explores the "deep mining" techniques that led to this disaster. He includes this excerpt of an Aug. 16 story in the New York Times:

...mining at extreme depth in Utah, where mine-produced tremors are common, creates a tapestry of forces that adds to mining’s inherent hazards.

First, the six men were working at a depth of more than 1,800 feet, which engineers say is where coal approaches its structural load-bearing maximum. Second, the coal itself, carved into large pillars within the mine, was essentially what held up the weight of the mountain above Crandall Canyon, near Huntington. Third, retreat mining involves removing or reducing the size of those pillars to extract as much coal as possible. Seismic jolts — called bumps or bounces in the language of miners — are often caused by compression of coal pillars and are most common in the deepest mines, like Crandall, where the pillars hold the most weight. Seven of Utah’s 10 operating mines, including Crandall Canyon, take miners to depths of 1,600 to 2,000 feet below the surface, said James Kohler, chief of the solid minerals branch of the federal Bureau of Land Management in Utah, which monitors mines on its lands. An eighth Utah mine is set to push through 1,800 feet in the next few years.

The days of easy, shallow coal are gone, Mr. Kohler said: “By necessity, we’re going deeper.”

So, more disasters of this type are just waiting to happen. despite what mine owner Bob "Crazy Guy" Murray said, there was no earthquake. The tremors were caused by the collapsing mine and the screams of the buried miners.

Another sign of the The Era of the New Robber Barons.