MSHA releases Crandall Canyon accident report
The United States Department of Labor's Mine Safety and Health Administration levied a record $1.85 million in fines July 24, against those they feel contributed to the August 2007 mine collapses at the Crandall Canyon mine.
In a press release issued by the DOL, it was reported that the operator of the mine, located in Emery County, was fined $1.34 million for violations that directly contributed to the deaths of six miners on Aug 6, 2007 and three more during the rescue operation on Aug.16, 2007.
Agapito Associates Inc.(AAI), a mining engineer consultant, was fined $220,000 for faulty analysis of the the mine's design.
MSHA then cited the mine operator for 11 additional noncontributory violations issued as the result of the investigation. The proposed penalty for those violations is $296,664, bringing the total proposed penalties against the mine operator to $1,636,664, a record for coal company fines, according to Department of Labor Assistant Secretary Richard Stickler. Crandall Canyon mine is operated by Genwal Resources Inc.(GRI), whose parent company is Murray Energy Corporation, according to the release.
Specifically, MSHA investigators cited GRI and AAI for the following violations:
â¢The mine operator did not immediately contact MSHA after coal outbursts threw coal into the mine openings and disrupted regular mining activities for more than one hour on three separate occasions prior to the Aug. 6, 2007 outburst.
â¢The mine operator failed to propose revisions to the roof control plan when conditions (coal outbursts) clearly indicated that the plan was inadequate and miners were being exposed to dangerous conditions.
â¢The mine operator violated the approved roof control plan by removing coal that was required to support the roof.
Comments made by Stickler and Richard Gates, District 11 Manager, alleged during the July 24, conference, that for reasons that have never been determined, GRI mined cuts from the barrier in the south barrier section between crosscuts 139 and 142 which were intended to be left unmined to protect the bleeder system.
â¢The mine operator's outside engineering firm failed to recommend safe mining methods and pillar/barrier dimensions. The operator also failed to maintain pillar dimensions that would effectively control coal outbursts.
MSHA and other government officials met with families of the deceased miners and the media on Thursday for more than five hours, meticulously detailing their findings during the nearly year long investigation.
According to the MSHA executive summary, on Aug. 6, 2007, at 2:48 a.m., a catastrophic coal outburst accident occurred during pillar recovery in the south barrier, while the crew was mining the barrier near crosscut 139. The outburst initiated near the section pillar line and propagated toward the mine portal.
"Within seconds, overstressed pillars failed throughout the south barrier section over a distance of approximately one-half mile. Coal was expelled into the mine openings on the section, likely causing fatal injuries to Kerry Allred, Don Erickson, Jose Luis Hernandez, Juan Carlos Payan, Brandon Phillips and Manuel Sanchez," stated the summary. "The barrier pillars to the north and south of the south barrier section also failed, inundating the section with lethally oxygen-deficient air from adjacent sealed areas, which may have contributed to the death of the miners. The resulting magnitude 3.9 seismic event shook the mine office three miles away and destroyed telephone communications to the section."
Following the incident, federal and local authorities responded to the accident. Acting within MSHA protocol, Genwal obtained and gained approval for a recovery and restoration plan. Mine rescue teams were organized, a command center was established and rescue efforts commenced. Attempts were made to reach miners by crawling directly to them and then loading burst debris from the south barrier section one and going in via continuous miner. Efforts began on Aug. 8, 2007 at crosscut 120, 19 crosscuts from the believed position of the trapped miners.
On Aug.16, 2007, at 6:38 p.m., a coal outburst occurred from the pillar between the number one and number two entries, adjacent to rescue workers as they were completing the installation of ground support behind the continuous mining machine. Coal ejected from the pillar, dislodged standing roof support, steel cables, chain-link and a steel roof support channel which struck the rescue workers and filled the entry with approximately four feet of debris, said the investigation report.
Once again air supply was an immediate problem as additional rescue workers began to dig out trapped individuals and repair ventilation controls. Two mine employees, Dale Black and Brandon Kimber were killed along with MSHA inspector Gary Jensen. Six additional rescue workers and an MSHA inspector, were also injured.
Further data provided by the report gives detailed explanation of the events, "The Aug. 6 collapse was not a natural earthquake but rather was caused by a flawed mine design. Ultimately, it is most likely the stress level exceeded the strength of a pillar or group of pillars near the pillar line that local failure initiated a rapid and widespread collapse that propagated outby though the large area of similar sized pillars," stated the report. "The extensive pillar failure and subsequent inundation of the section by oxygen-deficient air occurred because of inadequacies in the mine design, faulty pillar recovery methods and failure to adequately revise mining plans following coal burst accidents."
According to the report, engineering models used by the firm were labeled as "inappropriately applied" and "flawed," providing data and recommendations that overestimated pillar strength and underestimated load.
"AAI modeled pillars with cores that would never fail regardless of the applied load, which was not consistent with realistic mining conditions," states the summary. "They did not consider the indestructible nature of the modeled pillars in their interpretations of the results."
In addition to MSHA's contention of a flawed roof control plan, their report accuses that, "GRI's mining practices, including bottom mining and additional barrier slabbing between crosscuts 139 and 142, reduced the strength of the barrier and increased stress levels in the vicinity of the miners."
As pillars were recovered in the south barrier section, bottom coal, (a layer of coal left in the mine floor after initial mining) was mined from cuts made into the production pillars and barrier. The effect of this activity was to reduce the strength of the remnant barrier behind the retreating pillar line, furthermore, it was not addressed in AAI's model to evaluate the mine design or in GRI's approved roof control plan, as stated in the report.
The executive summary further accuses GRI of not reporting three coal outbursts that occurred prior to the Aug. 6 accident, and of not properly revising their mining plan following these events. On March 7, 2007 a non-injury coal outburst occurred that knocked miners down, damaged a ventilation control and caused delay in mining.
"Worsening conditions culminated in a March 10, 2007, outburst accident of sufficient magnitude to cause the mining section to be abandoned," states the summary.
On Aug. 3, 2007 another non-injury coal outburst accident occurred as the night shift crew was mining. GRI did not notify MSHA of these three coal outburst accidents within 15 minutes as required by statute, according to the report.
"GRI failure denied MSHA the opportunity to investigate these accidents and ensure that corrective actions were taken before mining resumed in the affected area," continues the summary. "GRI did not submit reports of these accidents to MSHA or plot coal bursts on a mine map available for inspection by MSHA and miners as required. These reporting failures were particularly critical because they deprived MSHA of the information it needed to properly assess and approve GRI's mining plans."
According to the report, the Aug. 16, 2007 accident occurred because rescue of the entrapped miners required removal of compacted coal debris from an entry affected by the Aug. 6, 2007 accident. Methods for installing ground control systems required rescue workers to travel near areas with "high-burst" potential.
"Methods were not available to determine the maximum coal burst intensity that the ground support system would be subjected to," explained the summary. "On Aug. 16, 2007, the coal burst intensity exceeded the capacity of the support system. No alternatives to these methods were available to rescue the entrapped miners. As a result, only suspension of underground rescue efforts could have prevented this accident."
The complete report is available at MSHA's website and gives more details about the root causes of both incidences.
As the press conference reached its question and answer period, reporters peppered MSHA concerning their role in the accidents. While mine safety officials would not comment about allegations into their accused negligence in the matter, an independent congressional investigation into MSHA's role in the Crandall Canyon tragedy is underway.
Following MSHA's officials statements and presentation, Kevin Anderson, representing GRI, read a prepared statement accusing the mining and safety administration of not gathering all the facts and falling victim to political posturing.
"This report does not have the benefit of all of the facts," said Anderson.
According to his statement, MSHA's chief lawyer predicted that parallel congressional probes would cause MSHA's investigation to become tainted, he stated:
"[The congressional] investigation poses an inherent threat to the integrity of [MSHA's] investigation. Your parallel investigation could prejudice the testimony of other witnesses, subject witnesses to possible intimidation, tip off potential civil or criminal violators that they are under suspicion and/or taint the investigation such that any enforcement action is precluded from being brought."
The GIR statement continues, "their [Congress] actions blocked MSHA from important sources of information and expertise, including mining engineering experts who have vital knowledge of Crandall Canyon's engineering and operations and who are at the center of MSHA's report.
The statements and subpoenas from members of Congress made plain that their own parallel investigations were directed more towards laying blame rather than finding the actual cause of the accident. As a result, some of these experts refrained from speaking with MSHA and Congress."
The statement claims that these men had extensive knowledge of the mine's operation, having worked there for decades before the UtahAmerican acquisition in 2006.
"Indeed, our mining plan and various roof control plans were grounded on their recommendations in conjunction with MSHA's independent review, approval and required modification," explains the statement.
MSHA will now present their findings to the United States Attorney General for consideration of possible criminal charges amid congressional and department of justice probes.