Markel Koon, 58, a 37-year mining veteran, was working at Consol's Robison Run No. 95 operation in Harrison County last November 30. Just after noon an embankment at the mine’s Nolan Run impoundment failed, sending the miner and his machine into the murky water to a depth of 27 feet.

While rescue efforts began immediately, the search eventually became one of recovery. Koon’s body was pulled from the dam two weeks later on December 14.

In its 16-page report released this week, the WVOMHST determined the embankment at the impoundment was not constructed or maintained to ensure safe operation of mobile equipment.

“The conditions of the impoundment deteriorated quickly … causing large sections of an approximately five-foot high wave of slurry to travel west to east, then return to the collapsed area of the saddle dike,” investigators said in the report.

Citing state code Chapter 22A, Article 2, Section 53(b)(18), the agency said Consol violated the regulation as a large section of the dump area became unstable, cracking and collapsing along with the Caterpillar D-6T and Koon, its driver.

Two other miners went into the water at the same time, though both were rescued without serious injury.

The section that failed was more than 600 feet long, 50ft wide and 24ft high.

Agency officials did not indicate any planned assessed fines in the report, though it did release multiple recommendations to the operation including training on water hazards and the use of life jackets by all working near the dam.

Investigators did not indicate if either would have been sufficient to save Koon’s life.

According to state data, the unionized 592-worker Robison Run operation near Shinnston has an average daily production of 19,045 tons.

Consol did not immediately respond to an ILN request for comment on the report.