CHARLESTON, W.Va. -- CONSOL Energy officials had been concerned about potentially troubling water-pressure readings for more than a week prior to the November 2012 collapse of a coal-slurry embankment that killed a miner, according to a state investigative report released Wednesday.
The state Office of Miners' Health, Safety and Training cited CONSOL's Consolidation Coal Co. subsidiary in the incident, which occurred at the Nolan Run impoundment at its Robinson Run Mine near Lumberport.
Dozer operator Markel Koon, 58, of Shinnston, was swept into the impoundment shortly after noon on Nov. 30, when a smaller "saddle dike" collapsed.
State investigators concluded that the embankment "was not constructed or maintained in a manner to ensure safe operation of mobile equipment."
"This is a violation of a health and safety statute of a serious nature involving a fatality," the agency said in a 14-page report provided to the state Board of Coal Mine Health and Safety during a meeting in Flatwoods.
The incident occurred on an embankment -- constructed of coarse coal refuse piled on top of finer coal slurry -- being built as part of a plan to expand the Nolan Run site so it could continue to accept waste from the nearby Robinson Run Mine's preparation plant.
A large section of the dike area "became unstable, then cracked and collapsed in the water and slurry" inside the impoundment, state officials said in their report.
Two other CONSOL employees who ended up in the impoundment managed to survive. Koon's body, still inside his dozer, wasn't recovered for more than a week.
The state's report cited company emails that indicate CONSOL had for at least a week been monitoring high water-pressure readings that could indicate the structure wasn't stable.
In one email, dated Nov. 24, a CONSOL official asked if the readings "mean we have to stop placing slate here until the pressure goes back down." In response, another company official wrote the next day that "the area should be monitored for a week or so to let it stabilize," the state's report said, paraphrasing both electronic messages.
State officials said Wednesday that it was possible the elevated pressure readings were not correct, because the monitoring equipment had been installed only a week earlier, on Nov. 16, and needed time to stabilize.
The state report cited another CONSOL email, sent at 11 a.m. the day of the collapse, indicating the pressure reading was the same as the week before.
CONSOL officials did not immediately respond to a request for comment.
In their new report, state investigators provide previously undisclosed details of what happened in the moments leading up to the embankment collapse.