“Massey, as well as UBB family members who want to get to the truth, are very excited to finally have our experts view the mine together,” chief operating officer Chris Adkins said.

“We have assembled some of the finest experts in the world, but to date they have not been free to investigate in a methodical, scientific way. Now, however, we are very close to being free to conduct a thorough investigation that will provide the answers that the families deserve.”

Massey is now awaiting approval from the US Mine Safety and Health Administration before the company probe can begin.

The company said that, to date, it has only been permitted to accompany state and federal officials in their investigations underground.

While serving as the day-to-day director of investigative efforts, MSHA has limited the number of participating Massey Energy individuals to one person per inspection team.

This move, Adkins said, has prevented explosion, geology, mining engineering, electrical engineering and mining ventilation experts from collaborating on cause and being joint investigative contributors at a point when time is crucial.

“Every day, evidence is deteriorating,” he said.

“We need MSHA to approve our plan quickly, as the state has done.”

MSHA lead investigator Norman Page said Massey would be allowed to conduct its own investigation after the federal probe was completed.

The agency reported last week that its underground review is now approximately 90% complete, leaving the producer waiting for approval to investigate areas already logged by federal officials.

MSHA spokesperson Amy Louviere told ILN the agency is reviewing the plan and expects to meet with the company on Tuesday regarding its contents.

“MSHA must carefully review this plan before considering any modifications to its section 103(k) order at Upper Big Branch Mine-South, so as to ensure the safety of miners and investigators underground,” she said.

In related news, state officials said they are hoping to wrap up their probe into the incident by the middle of next year.

West Virginia Office of Miners’ Health, Safety and Training director Ron Wooten told Associated Press the date is just a goal, as he has told his investigators to take as long as they need to complete their work.

The state investigation is being conducted in conjunction with MSHA’s probe; federal officials have not indicated when they plan to complete their review.

Keep watching ILN for more details on the UBB explosion investigations.