There were many factors that led up to the April 5, 2010, explosion that killed 29 coal miners at Massey Energy’s Upper Big Branch (W.Va.) mine, according to a new Mine Workers (UMWA) report on the disaster. But according to the report—”Industrial Homicide“—“there is only one source for all of them:”

A rogue corporation, acting without real regard for mine safety and health law and regulations, that established a physical working environment that can only be described as a bomb waiting to go off.

And that same company established a working environment where, operating through subterfuge, fear and intimidation, management prevented any opportunity for the workers to know the full range of dangerous conditions in the mine, or to effectively protest them even if they did know.

Upper Big Branch was a nonunion mine, but following the explosion miners and their families asked the UMWA to be their designated representative in the investigation. The final Mine Safety and Health Administration (MSHA) report will be released later this year.

The UMWA report says management at Upper Big Branch (UBB) “deliberately flouted” well-established safety and health laws even after the mine was cited multiple times by state and federal agencies.

The only conclusion that can be drawn is that Massey simply did not care if it broke the law. The safety of its employees was not worthy of its concern. The only thing that mattered was getting the coal out.

This attitude was not a creation solely of management at the UBB mine. Far from it. This was a company-wide practice, fomented and directed by those at the highest corporate levels.

In February, Alpha Natural Resources bought Massey Energy for $8.5 billion.

But the report also criticizes both state agencies and the Bush-era federal mine safety administration, saying it was “unconscionable” that they allowed Upper Big Branch to be operated the way it was.

They failed in their responsibilities to be effective and thorough enforcers of the law.

The 154-page, highly detailed and technical report (click here to download) says the powerful blast occurred after a long wall-cutting machine encountered a pocket of methane gas that had built up because of a lack of adequate ventilation. A spark from the machine’s worn cutting bits ignited the methane and the machine’s faulty water sprayers failed to contain it.

The initial blast then encountered a mine atmosphere ladened with highly explosive coal dust that had been allowed to accumulate to dangerous levels—despite citations from both MSHA and the West Virginia Office of Mine, Health Safety and Training.

The dust fueled a blast that was so powerful that it traveled more than seven miles underground, destroying hundreds of ventilation controls and miles of the beltline that carries coal to the surface, and hurled heavy equipment throughout the mine.

The report concludes that Massey Energy “must be held accountable for the death of each of the 29 miners.”

Theirs is not a guilt of omission, but rather, based on the facts publicly available. The Union believes that Massey Energy and its management were on notice of and recklessly tolerated mining conditions so egregious that the resulting disaster constituted a massive slaughter in the nature of an industrial homicide.