CAMP PENDLETON, Calif. — Two Marines have been relieved after a report found that the explosion that killed four explosive ordnance disposal Marines here in November was likely caused when a 40-millimeter round was “dropped, kicked or bumped” in the demolition pit.
Staff Sgt. Mathew R. Marsh, Gunnery Sgt. Gregory J. Mullins, Sgt. Miguel Ortiz and Staff Sgt. Eric W. Summers died Nov. 13 after the explosion at Zulu impact area. The investigation could not establish exactly what caused the round to go off, said Capt. Ryan Welsh, a spokesman for the base.
“We’ll never know the exact cause,” Welsh said.
The officer in charge and the staff noncommissioned officer in charge, a Marine captain and master sergeant, have been relieved for a “loss of trust and confidence in their ability to ensure proper preparation for and conduct of EOD proficiency training and lack of adherence to the established norms,” according to the Marine press release.
The four Explosive Ordnance Disposal Marines were clearing the range of unexploded ordnance and consolidating it as part of an annual training exercise, according to a Marine report about the results of the investigation. The Marines moved 40-millimeter rounds into one area surrounding an M60 105-millimeter white phosphorous round that could not be safely moved, the investigation found. They were moving rounds from the consolidation point to the demolition pit when one of the rounds exploded in the demolition pit, causing the other 40-millimeter rounds at the consolidation point and the demolition pit to explode, the investigation found.
The M430/A1 40-millimeter high explosive dual purpose round is fired from a Mark 19 grenade launcher.
Brig. Gen. John Bullard, commanding general of Marine Corps Installations West-Marine Corps Base Camp Pendleton, initiated the command investigation. He also has called for an immediate review and revision of policies and procedures for EOD training at all ranges under the Marine Corps Installations West umbrella.
“Many of the training evolutions we conduct are inherently dangerous, especially when dealing with explosives and munitions,” said Bullard. “We are deeply saddened by the tragic loss of four Marines during a training evolution; their loss is felt throughout the Marine Corps. We offer our heartfelt prayers and thoughts to the family members, and will continue to support them through this difficult time.”