The report accused Murray Energy, which operated the mine, of:

* Not formally reporting a March 11 "bounce" that dislodged so much coal that mining was terminated abruptly in the North Barrier Pillar, just 900 feet from where August's tragedy occurred.

* Rushing ahead with a similar mining plan in the South Barrier Pillar even though the engineering calculations of its consultant, Agapito Associates Inc., were based on inaccurate mine-depth data and overestimated the strength of coal pillars left behind.

* Failing to document repeated collapses of coal from walls and roof falls in pre-shift books monitored by MSHA and required by law.

* Disregarding safety, as reflected in an increasing rate of "serious and substantial" violations and a "blanket policy of contesting all MSHA safety citations, regardless of the merits."

* Trying to intimidate MSHA officials in Price and Denver immediately after acquiring the mine in August of 2006. Wrote MSHA District Manager Allyn Davis to a colleague: "I expected we would have trouble with this operator, but didn't expect it on the second day after they took over [the mine]."

The report also was critical of MSHA for:

* Not taking a conservative, cautious approach to approving the company's mining plan given the "extreme risk" posed by retreat mining at depths never before allowed.

* Not thoroughly reviewing the plans' engineering underpinnings. When MSHA engineer Pete Del Duca challenged the plans, his superior rejected his concerns based on the response of Murray Energy officials.

* Failing to submit the Crandall Canyon mining plans to roof control specialists in MSHA's safety and health technology center.

* Ignoring the law by not requiring Murray Energy to report bounces that interrupted work, allowing the company to ignore that mandate unless a miner got hurt.

* Not talking to the federal Bureau of Land Management about that agency's observations of troubling conditions underground.

* Never seriously looking into an anonymous complaint during Christmas week of 2006 that "no attention was being given to safety" at Crandall Canyon. An inspector agreed and requested an investigation to determine if mine officials knowingly and willfully violated safety regulations, but the request was not acted upon.