The federal government says coal company Matrix Energy LLC is to blame in the death of a Martin County miner.Fifty-four year old veteran miner Robert L. Cook was killed last March when he was crushed between machinery and the mine, and in the report, the Mine Safety and Health Administration concluded his death was preventable.MSHA's investigation concludes the mine—operated by Matrix Energy LLC—didn’t have adequate training and safety policies in place at the time of the accident. The mine was cited for violations, and voluntarily installed a proximity detection system on two of its continuous miners.MSHA has issued a proposed rule to require mines to install similar devices that would stop dangerous machinery when someone comes too near, but it hasn’t been finalized yet.