May pleaded guilty last year to a conspiracy charge of defrauding the Federal Bureau of Investigation and the US Mine Safety and Health Administration by falsifying records and disabling a gas monitor.

Up until now he had been cooperating with officials’ ongoing criminal probe into the blast but US district judge Irene Berger still sentenced him on Thursday morning to one felony count of conspiracy, according to an Associated Press report.

The maximum penalty for the charge was five years in prison but the sentence is at the top of the 15-to-21-month range recommended by federal sentencing guidelines.

Just last week, through his attorney Tim Carrico, May asked for a lenient sentence such as probation or home confinement.

Carrico reportedly said in court documents that his client was “deeply sorry” about the miners who died but did not see a direct link between the explosion and his conduct.

He cited May’s cooperation with officials who were still seeking answers in the UBB criminal investigation.

Prosecutors, meanwhile, had been pushing for a sentence at the top or even exceeding the guideline range, citing “risk to human life and health” from violations like those included in his plea agreement.

“Common sense dictates that when a defendant risks other people's lives and health, that fact must be accounted for in fashioning his sentence," assistant US attorney Steve Ruby told the AP.

“To treat this conspiracy, with its risk of death or injury to others, like routine conspiracies whose risk is only financial would understate the seriousness of this offense.”

May initially pleaded guilty last March to conspiracy to impede the MSHA in its enforcement efforts at the Raleigh County operation between February 2008 and April 5, 2010 – the day of the blast.

He said he had plotted with “others known and unknown" to conceal hazards at UBB and place production ahead of worker safety.

May also admitted that in February 2010, just two months prior to the explosion, he ordered the alteration of the electrical wiring of a continuous miner methane monitor to override the automatic shut-off of the machine that was typically triggered by high methane levels.

Last April, the US Attorney’s office began an investigation into whether federal officials might have provided warning to Massey Energy of upcoming inspections.

It followed a March 29 testimony by 43-year-old May when he entered his plea.

According to media reports, at the hearing Berger asked May who else played a role in the conspiracy to hide safety violations by working with others to provide advance notice that an inspector was onsite at the mine.

“It started, you know, from the MSHA inspectors coming on the property,” May testified, according to the Associated Press.

“Sometimes they would tell us, you know, they'd be back tomorrow or where they were going.

“And it went from there to telling everybody that was outside, you know, just scatter word by mouth on the phone and they would tell whoever was underground.”

He also told Berger in March that the practice by federal inspectors occurred for his entire tenure at UBB, as well as every mine he had ever been to.

Federal regulations under the Mine Safety and Health Act prohibit the advance notice of inspections by anyone, be it mine employees to others or on the part of its own federal inspectors.

May is not the first to be handed down punishment for his role in the incident.

Former security chief Hughie Elbert Stover is in a Kentucky prison following his conviction for lying to investigators and ordering the destruction of documents during federal officials’ investigation.

Former White Buck Coal subsidiary president David Hughart is expected to enter a plea to two federal conspiracy charges late next month – he was initially scheduled for a hearing earlier this week but it was delayed.

He has been accused of working with co-conspirators to ensure miners and other still-unidentified Massey operations received advance warning about surprise federal inspections from 2000 to 2010.

Hughart has also been cooperating with authorities, which some consider as a sign that other officials from the Massey Energy hierarchy may be the next targets.