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The Crandall Canyon Mine, formerly Genwal Mine, is an underground bituminous coal mine in northwestern Emery County, Utah.

Location

The Crandall Canyon Mine is located at 39°27′36″N 111°10′03.5″W / 39.46000°N 111.167639°W / 39.46000; -111.167639Invalid arguments have been passed to the {{#coordinates:}} function (39.460000°, -111.167639°)Template:GR with its entrance at an elevation of 7,385 feet (2,251 m). It resides in Emery County, Utah, about 15 miles (24 km) west north-west of Huntington. Located just off Utah State Route 31, is about 34 miles (55 km) southeast of Fairview, and 140 miles (225 km) south of Salt Lake City. The mine is within Crandall Canyon in the Wasatch Plateau Coal Field.^[1] The permit area for the mine covers an area of more than 5,000 acres (2,023 ha) utilizing fee land, federal, and state leases.^[1] The Manti-La Sal National Forest surrounds the mine. The mine conducts surface operations on 10 acres (4 ha) of disturbed land within the forest.^[1]

Ownership and operation

The mine is owned by UtahAmerican Energy, Inc. (formerly Andalex Resources), a company with approximately US$65.1 million in annual sales, headquartered in Sandy, Utah. UtahAmerican is a subsidiary of Cleveland, Ohio based Murray Energy Corporation, owned by Robert E. Murray.^[2]^[3] The Crandall Canyon mine is operated by Genwal Resources Inc., an operating division of UtahAmerican.

History

Mining was conducted at the site from November 1939 to September 1955 using a room and pillar method.^[1] The Genwal Coal Company resumed mining there in 1983.^[1] At that time the mine produced between 100,000 and 230,000 tons (91,000 t - 209,000 t) of coal each year.^[1] NEICO purchased the mine in 1989 and the next year IPA purchased 50% interest.^[1] By 1991, a continuous haulage system was used helping production surge to 1 to 1.5 million tons (900,000 t - 1,400,000 t) each year.

Genwal Resources, Inc. acquired the mine in March 1995 and a longwall was installed the same year into the mine.^[1] The installation of the longwall nearly doubled the capacity of the mine.^[1] A new longwall was purchased two years later which increased the capacity further to 3.5 million tons (3,175,000 t) per year.^[1] To handle the increased capacity, a new loadout facility was built at the mine.^[1] Additional federal leases were expected to extend the life of the mine and new portals on its south side were slated to be installed to expand access options.^[1]

Safety concerns

In 2006 the mine had been cited for several safety violations, including lacking the required number of escape routes.^[4] In addition, a practice referred to as retreat mining was common at the mine. Normally miners leave large columns, or pillars, of coal in order to support the mine entry. This is known as room and pillar mining, because the extraction of material literally creates a 'room' while leaving occasional pillars of coal to support the ceiling. Retreat mining refers to the common practice of removing the pillars after room and pillar mining while retreating back towards the mine entrance. This allows the roof, or back, to collapse and settle and must be carried out in a specific pattern while retreating back toward the original entrance.

Collapse

File:08092007 CrandallCanyonMine.jpg

Workers attempt to reach the trapped miners.

On Monday, August 6, 2007, at 2:48 A.M. MDT, the mine collapsed, trapping six workers inside. The workers are: Kerry Allred (50), Luis Hernandez (23), Brandon Phillips (24), Carlos Payan (20s), Manuel Sanchez (41), and Don Erickson (50). The workers are believed to be approximately 3.4 miles (5.5 km) from the mine entrance and 1500 feet (457 m) underground. The collapse registered recorded seismic waves in magnitude 3.9 to 4.0 by seismograph stations in Utah and Nevada. Initial reports questioned if the collapse was triggered by an earthquake, but overwhelming evidence has led researchers to believe the seismic waves were caused by the collapse ^[5]^[6]. Additional seismic activities were recorded in the days following the event.^[7]^[8]^[9]^[10]

Disaster response

Rescue teams were immediately dispatched to assess the damage to the mine and begin clearing rubble to reach the cavity. The process of clearing the rubble and reinforcing the passageways to the cavity is expected to take between two to six weeks, however additional seismic activity and safety concerns have introduced further delays.^[11]

At 9:47 PM MDT Thursday August 9, 2007, a drill bit boring a 2.5 inch (6.3 cm) hole over 1,800 feet (549 m) into the presumed location of the trapped miners finally reached its targeted destination.^[12] The hole was fitted with a steel pipe to allow air samples to be recovered and a microphone to be lowered, which reached the cavity location underground early Friday morning on August 10. The microphone recorded no sounds of human activity, but the crude air sample analysis from underground initially determined that the atmosphere was hospitable for life, with a sampling consisting of 20.5% oxygen, some carbon monoxide, and no traces of methane.^[13] The analysis did not, however, reveal the presence of carbon dioxide, which would have signaled a fair to good chance that the miners were still alive and breathing. Subsequent air samples, though, showed oxygen levels near 7%, at near fatal levels for human life.^[14] Initially, the subsequent sampling was thought to be consistent with a neighboring sealed-off mine cavity, and that the drill bit simply drifted off course, but it was later confirmed that it actually did reach its targeted destination. Seemingly, the initial findings of 20.5% oxygen levels were from the bore hole itself, instead of the actual mine cavity.^[15]

Concurrently, another rescue effort took place, involving the creation of a nine-inch (22 cm) hole. The target was another supposed underground location of the miners at the time of the collapse. This shaft would allow the delivery of food, water, and a powerful camera to scope the site. This shaft reached the mine shaft early Saturday, August 11.^[16] The aforementioned video camera was lowered into the collapsed coal mine from the nine-inch wide shaft, and revealed typical mining equipment but not the six missing miners, according to a federal official speaking on Sunday, August 12, 2007.

Poor lighting allowed the camera only to see about 15 feet (4.6 m) into a void at the bottom of the drill hole, far less than the 100 feet (30.5 m) it is normally capable of seeing, said Richard Stickler, Chief of the Mine Health and Safety Administration.

A third bore hole was started on the evening of Sunday, August 12th. The target is a ventilation area near the back of the mine. Miners are trained to go to these areas in the event that other escape routes are inaccessible. The bore hole was completed mid-day on Wednesday, August 15th.^[17] Initial equipment was unable to fit through a bend in the bore hole.

Shortly before 7:00 pm MDT on August 15, 2007, CNN reported there were sounds heard in the mine.^[18] These sounds had a duration of around five minutes, but could easily have be an animal or even a rock crumbling, said Stickler. This sound activity caused a major rethinking in the proposed location of the fourth hole that was under consideration.^[19] This fourth hole will target these noises detected in the mine about 3/4 of the distance to he third hole, roughly 800 feet (250 m) beyond the initial holes. ^[20] The first two bore holes targeted the approximate location of the miners at the time of the collapse. The third bore hole targeted a ventilation area about 1200 ft (365 m) beyond the first two holes.

As of mid-day August 16, 2007, eleven days after the collapse, underground rescue teams are less than halfway through the rubble to the suspected location of the miners. Continued seismic activity has damaged digging equipment and additional structural reenforcement for the safety of the crew. In the 24 hours between the August 15th and 16th reports, digging teams were only able to advance about 25 feet (7.5 m) with their progress slowed due to increased seismic activity and equipment repair. They have advanced 826 feet (251.7 m) into the rubble and estimate 1200 feet (365 m) still remain. ^[21]

Second disaster during rescue efforts

As of August 16th, 2007 at 8:00pm MDT, there was a major accident involving the rescue workers. Details are speculative at this point, but officials are reporting that at least 7 rescue workers were injured (along with three fatalities) in another mine collapse. [1]

Timeline

On Thursday, August 16th, 2007

At 8:55pm MDT: CNN reported that at least six ambulances were dispatched to the mine following a "significant seismic event" or "bump". A seismic event was registered at 6:38 in that area^[22]. in which several rescuers were injured, according to a representative from the Utah Department of Natural Resources^[23]. Two helicopters were also dispatched from University of Utah Hospital in Salt Lake City. Deseret Morning News further reported that the same official, Tammy Kikuchi, stated that five people were injured, two critically^[24].

At 9:22pm MDT: MSNBC and KSL-AM were reporting nine injuried and with two of those critical. ^[2]

At 9:57pm MDT: KSTU confirmed reports of one fatality among the rescuers following a "bump" at about 6:30pm (KSTU also reported a 1.6 magnitude seismic shock occuring (recorded by the University of Utah also at around 6:30pm).

At 10:57pm MDT: CNN & AP reported that a second rescue worker has died.

At 11:40pm MDT: CNN reported that a 3rd rescue worker has died.

On Friday, August 17th, 2007

At 1:50am MDT: CNN reported that one injured rescue worker has been released from the hospital.

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