retreat mining

The bureau of land management says retreat mining was being used.

However, this can be extracted at a later stage (see retreat mining).

The measure would require more thorough review and monitoring of retreat mining plans.

That increased incentives for mine owners to order dangerous "retreat mining."

And the report said the agency had not shown it was free of “undue influence” from mine owners in approving retreat mining.

Retreat mining is often the final stage of room and pillar mining.

But the pattern of weak oversight, they said, was clear in how retreat mining was considered, approved and monitored.

In this context, longwall mining can be classified as a form of retreat mining.

Retreat mining refers to the common practice of removing the pillars while retreating back towards the mine entrance.

Miller took the opportunity Monday to promote legislation awaiting Senate approval that he said would strengthen government reviews for retreat mining.

Retreat mining involves yanking supporting pillars of coal from the mine, allowing the roof to collapse as miners and equipment work their way out.

Bulk mining methods such as vertical crater retreat mining, which doubled productivity, were pioneered under his guidance.

Retreat mining is a term used to reference the final phase of an underground mining technique known as room and pillar mining.

Murray Energy chief Bob Murray has insisted that taking down the pillars, a practice called retreat mining, had nothing to do with the collapse.

The finding is yet another reason why Congress must urgently pass a mine safety bill that would mandate more stringent oversight of retreat mining and other needed reforms.

Murray conceded after the collapse that retreat mining had been done at Crandall, but said the practice was not being used at the time of the cave-in.

"Retreat Mining" Abandoned Mine Posts.

Stricklin said his engineers are trying to determine if retreat mining can be done safely in Utah, where the geology under mountain ranges is fraught with danger.

Allied operates the Bellambi West colliery which mines the Bulli seam coal by the long wall retreat mining method.

About 25 percent of deaths involving coal miners happen during retreat mining, Mine Safety and Health Administration spokesman Jesse Lawder said.

The House committee, which began its inquiry within weeks of the disaster, hired Norwest Corporation, an engineering firm, to review the mine and its retreat mining plans.

In longwall mining and retreat mining, miners systematically remove all support from under large areas of the mine roof, allowing it to settle just beyond the work area.

Although the widely used industry practice of retreat mining is believed by some observers to be a cause of the mine's 2007 collapse, Murray insists the process was not responsible.

The pair had been retreat mining, a process considered dangerous because it involves removing of the last resources from an area of the mine shortly before support pillars are taken out.

In addition, a practice referred to as retreat mining was being conducted in some portions of the mine in which the coal had been removed by room and pillar method.