MULLAN, Idaho -

The family of Larry Marek and federal investigators are saying that aggravated negligence killed the lifelong miner at the Lucky Friday Mine on April 15.

The collapse at the mine happened after managers ordered a pillar holding up the roof of the tunnel removed so they could get more silver to the surface.

Marek's daughter Hayley says the pillar was taken out because it was worth too much money to leave behind.

Mine Safety and Health Administration officials say Marek was working in an unusually wide tunnel, one that needed a pillar to help hold up the roof. The investigators found "a substantial quantity of material fell on Marek after portions of that supporting pillar was removed to extract ore."

The amount of rock that came down was the size of two buses stacked on top of each other.

Inspectors say that's clearly a sign "ground support was necessary in the stope to mine safely but the ground support utilized was not adequate."

That's why mine safety investigators wrote, "mine management has engaged in aggravated conduct constituting more than ordinary negligence by directing the pillar to be mined as the stope advanced."

Hayley Marek took the allegation one step further by writing in a comment on kxly.com earlier this week that "[t]here were miners that felt this was unsafe and management did not listen. They did expose my father to an unsafe situation. They removed a support pillar that was high in ore."

In their narratives of these two citations against Hecla, owner of the Lucky Friday Mine, MSHA officials also flagged the pillar removal and subsequent lack of support as potential flagrant violations.

For those violations, Hecla could be fined up to $22,000 for each violation.

Hecla officials continue to decline comment on these allegations until the MSHA investigation has been completed.