Don Blankenship, the former Massey Energy chief executive. (F. Brian Ferguson/The Gazette-Mail via AP)

The former chief executive of a company that owned a West Virginia mine where 29 miners were killed in a 2010 explosion was sentenced Wednesday to a year in federal prison.

Don Blankenship, who had been chief executive of Massey Energy, was found guilty by a jury in December on a charge of conspiracy to willfully violate mine health and safety standards. He was sentenced one day after the sixth anniversary of the accident, which drew national attention and prompted congressional scrutiny.

The year in prison was the maximum sentence for this charge. Blankenship was also ordered to pay a $250,000 fine and sentenced to a year of supervised release.

“This sentence is a victory for workers and workplace safety,” Carol A. Casto, the acting U.S. attorney for the Southern District of West Virginia, said in a statement after the sentence was handed down. “It lets companies and their executives know that you can’t take chances with the lives of coal miners and get away with it.”

The massive coal dust explosion at the Upper Big Branch coal mine, located south of Charleston, was later declared by federal authorities to be the country’s worst coal mining disaster in decades. Before the explosion, the mine had been written up dozens of times for safety violations.

In addition to the 29 miners killed in April 2010, two were seriously injured. This disaster occurred because of “a series of basic safety violations,” the Mine Safety and Health Administration later determined in a damning report. 

Federal authorities said their investigation found “multiple examples of systematic, intentional, and aggressive efforts” by the mine’s owners and operators “to avoid compliance with safety and health standards, and to thwart detection of that non-compliance by federal and state regulators.”

Another investigation into the explosion, this one commissioned by then-West Virginia Gov. Joe Manchin (D), concluded that “the explosion was the result of failures of basic safety systems identified and codified to protect the lives of miners.”

The Upper Big Branch Miners monument in Whitesville, W.Va. (Rick Barbero/Register-Herald via AP)

Because the company’s ventilation system could not properly ventilate the mine, “explosive gases” were allowed to accumulate, the report stated. In addition, the investigation found that poor maintenance of water sprays meant that “a small ignition could not be quickly extinguished.”

“The explosion at the Upper Big Branch mine could have been prevented,” the report stated.

On Tuesday, Manchin, now a U.S. senator representing West Virginia, said he hoped the sentence would bring some peace to the relatives of the miners killed in the accident.

“No sentence is severe enough, and no amount of time in jail…will heal the hearts of the families who have been forever devastated, and I pray that this sentence brings them some closure,” Manchin said in a statement.

Blankenship, who retired by the end of 2010, was a high-profile and controversial figure even before the disaster. He was indicted in 2014. During the jury trial in the fall, more than two dozen witnesses — many of them coal miners who had worked at Upper Big Branch — testified about the dangerous working conditions.

The sentencing of a former coal chief executive is a rarity and comes at a time when the industry has floundered amid environmental concerns and cheap natural gas prices. Massey Energy was purchased by Alpha Natural Resources in 2011, but that company itself filed for bankruptcy last year.

When Blankenship was found guilty last year, R. Booth Goodwin II, who was then the U.S. attorney for the Southern District of West Virginia, called it “a landmark day” for the country. Goodwin said it was the first time he knew about where a chief executive of a major company was “convicted of a workplace safety crime.”

Before he was sentenced, Blankenship spoke to the court. He expressed his sorrow for families that lost people at the mine and maintained his innocence, the Charleston Gazette-Mail reported.

“There was no direct evidence I committed a crime,” Blankenship said, according to the Gazette-Mail. “I am not guilty of a crime.”

After the sentencing, relatives of people killed in the explosion said they were outraged by the apology and the length of Blankenship’s sentence.

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William W. Taylor, an attorney for Blankenship, said Wednesday that he plans to appeal the conviction, and they expect an appeals court to reverse it.

“The jury rejected the most serious of the charges, as it should have,” Taylor wrote in an email Wednesday. “Mr. Blankenship feels a certain relief to have this phase behind him.”

Further reading:

Obama administration announces moratorium on new coal leases

A huge coal miners’ pension plan is on the brink of failure. One senator is blocking a fix.

Chris Mooney contributed to this report, which has been updated.