A former Massey Energy executive who admitted to helping hide safety violations at the company was sentenced Tuesday to 3 ½ years in prison – a year longer than the term recommended under federal sentencing guidelines.

In handing down the sentence against David C. Hughart, 54, U.S. District Judge Irene Berger said the stiffer sentence was meant to deter other mining officials from conspiring to violate U.S. Mining Safety & Health Administration (MSHA) standards, as Hughart admitted to doing.

"This sentence will promote respect for the law," Berger said.

Hughart, who pleaded guilty to two felony charges related to a conspiracy to circumvent MSHA inspections and violate its standards, will serve three years of supervised release after his prison term.

An explosion at Massey’s Upper Big Branch Mine in West Virginia killed 29 miners and set into motion a federal probe that appears to be nowhere near over.

Former UBB superintendent Gary May and security director Hughie Elbert Stover both received prison terms for their roles in concealing safety hazards at the mine and obstructing the government investigation into the disaster. Former miner Thomas Harrah was sentenced to ten months in jail for using a fraudulent foreman’s license to perform safety inspections at the mine and lying to investigators.

Former Massey CEO Don Blankenship has denied any wrongdoing in the incident.

Massey Energy was sold to Alpha Natural Resources in June 2011.