Upper Big Branch

05/04/2010 - Upper Big Branch - Explosion / Methane Explosion, Coal Dust Explosion

On April 5, 2010, at approximately 3:02 p.m., a massive coal dust explosion occurred at the Upper Big Branch Mine-South (UBB), killing 29 miners and injuring two. UBB is operated by Performance Coal Company (PCC), a former subsidiary of Massey Energy Company (Massey) (together PCC/Massey), and is located in Montcoal, West Virginia.

This tragic explosion was the largest coal mine disaster in the United States in 40 years.

The 29 miners who perished at UBB died in a massive coal dust explosion that started as a methane ignition. The physical conditions that led to the explosion were the result of a series of basic safety violations at UBB and were entirely preventable.

The investigation also revealed multiple examples of systematic, intentional, and aggressive efforts by PCC/Massey to avoid compliance with safety and health standards, and to thwart detection of that non-compliance by federal and state regulators.

PCC/Massey established a practice of using staff to relay advance notice of health and safety inspections to mine personnel when federal and state inspectors arrived at the mine. The advance notice allowed PCC/Massey employees to conceal violations from enforcement personnel. PCC’s chief of security was convicted in federal court for lying to MSHA about whether advance notice was a practice at UBB; the evidence at the trial showed that it indeed was a practice and he had directed UBB personnel to provide advance notice of inspectors’ arrival on the mine property.

Had PCC/Massey followed basic safety practices, the small methane explosion that set off the dust explosion would have been contained or prevented. PCC/Massey did not take proper measures to detect methane concentrations throughout the mine. PCC/Massey’s failure to comply with UBB’s approved ventilation and roof control plans exacerbated the risk of methane accumulation.

Its failure to install supplemental roof supports as required by UBB’s plan led to a roof fall in an airway that limited airflow, contributing to the accumulation of methane in the area where the explosion originated. Finally, PCC/Massey violated fundamental safety standards by permitting significant amounts of float coal dust, coal dust, and loose coal to accumulate in the mine. This became the fuel for the explosion. Sufficient rock dust, used to make coal dust inert and prevent it from catching fire or fueling an explosion, would have prevented a coal dust explosion from occurring. PCC/Massey did not follow the fundamental safety practice of applying rock dust adequately to eliminate this hazard.

This accident claimed the lives of 29 people.