Rescue workers entered the Upper Big Branch Mine in Montcoal this morning to search for the four miners still unaccounted for after Monday’s explosion, but they were called back out when air sampling showed unsafe air quality.

Reporters, members of Congress, and mine-safety advocates are scrutinizing the record of Upper Big Branch, and they’re finding a troubling pattern. Steven Mufson, Jerry Markon, and Ed O’Keefe write in the Washington Post:

The West Virginia mine where at least 25 workers died Monday in an explosion was written up more than 50 times last month for safety violations. Twelve of the citations involved problems with ventilating the mine and preventing a buildup of deadly methane.

… Three miners have died there since 1998, and the federal Mine Safety and Health Administration cited Upper Big Branch for 1,342 safety violations from 2005 through Monday, proposing $1.89 million in fines, according to federal records.

Sam Hananel and Tim Huber of the Associated Press report that in January, the mine received two of the heftiest fines in history for problems with a ventilation system that caused dirty rather than fresh air to be directed into an escapeway. Mine foreman Terry Moore told MSHA officials that the problem had been going on for three weeks; records show the problem was fixed on the day of the citation, but MSHA considered it an “unwarrantable failure,” the most serious violation type.

According to Hananel and Huber, MSHA inspectors cited the mine on the very day of the explosion for inadequate escape-route maps and an improper cable splice on a piece of electrical equipment. MSHA’s Kevin Stricklin expressed confidence that these violations were not involved with the blast.

News of so many violations – and so many of them pertaining to ventilation, which is crucial for preventing explosions – might make readers wonder whether a mine can be shut down for dangerous conditions. The Charleston Gazette’s Ken Ward Jr. delves into that issue, reporting that MSHA issued 54 withdrawal orders to Upper Big Branch in 2009, and seven to date in 2010. He explains:

Under federal law, MSHA generally does not have broad authority to simply close a troubled coal mine, unless it seeks a federal court injunction to stop anything its inspectors believe “constitutes a continuing hazard to the health and safety of miners.”

But, on its own authority and without going to court, MSHA can issue what the law calls “withdrawal orders” that force all miners to be removed from areas until significant hazards are eliminated.

In the case of the Upper Big Branch Mine, most of the withdrawal orders — 48 in 2009 and six during the first three months of this year — were issued when inspectors found Massey subsidiary Performance Coal exhibited an “unwarrantable failure” to comply with federal health and safety standards.

One of the most series withdrawal orders was issued in December 2009 under a section of federal law that allows inspectors to respond to “imminent danger” that “could reasonably be expected to cause death or serious physical harm.”

Ward also notes in a blog post that MSHA cited Massey for similar problems with inadequate escape-route maps and incorrect air flow in its Aracoma Alma No. 1 Mine – where a fire in January 2009 killed miners Donald Bragg and Ellery Hatfield.

Massey Energy evidently failed to learn the necessary lessons from that disaster. Will this disaster teach them, or MSHA, enough to prevent more tragedies like this one?