The Department of Justice must “go up Massey’s chain of command as far as possible” and hold accountable those individuals responsible for the deaths of 29 coals miners at Massey Energy’s Big Branch (W.Va.) mine in 2010, a group of lawmakers urged Attorney General Eric Holder.

In a letter to Holder from Rep. George Miller (D-Calif.) and 15 other House members, they say that although the recent settlement between the federal government and Alpha minerals—which took over Massey several months after the deadly disaster—includes a non-prosecution agreement with Alpha in exchange for $210 million in investments in mine safety and research, civil penalties and restitution to families,

It does not prevent the Department of Justice from investigating or bringing criminal charges against the individual’s responsible for the April 5, 2010 disaster.

The Mine Safety and Health Administration’s (MSHA) investigation of the blast found that individuals acting both alone and in concert were responsible for the unsafe mining practices and conditions that led directly to the explosion.

Though these individuals stood at the head of the disaster, they have thus far escaped justice.

Former Massey CEO Donald Blankenship and 18 other officers and non-employee directors were entitled to $196 million in the merger agreement with Alpha and lawmakers say that “dwarfs the $46. 5 million in civil restitution provided for survivors under the non-prosecution agreement.”

The lives of those affected will never be made whole, but you can continue to investigate to ensure that those who acted criminally will be prosecuted to the full extent of the law.

Click here for the full letter.