The CEO of the coal company that ran the mine where 25 miners died and four are missing thinks the mine was “safe to operate.” The explosion on Monday and the mine’s safety record indicate otherwise:

The mine 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.

Interviewed on CNN Wednesday morning, Massey’s president and chief executive, Don L. Blankenship, asserted that the hundreds of citations the mine has received for safety violations were neither excessive nor significant. He said that officials “knowledgeable” about the mining industry “had concluded that the mine was safe to operate.”

Federal regulators and members of Congress said they would examine the safety history of the coal mine south of Charleston, the site of the worst U.S. mining accident in at least a quarter-century. Massey Energy says on its Web site that the company’s safety record has been better than the industry average for six consecutive years, with its workers losing less time on the job through work-site accidents than its competitors. But in seven of the past eight years, Upper Big Branch miners lost more time on the job through work-site accidents than did other miners nationally, federal records show.

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.

That record “is a sign that they are not fixing their safety problems,” said Celeste Monforton, a former senior official at the Mine Safety and Health Administration. It is not unusual for a mine to receive a substantial number of citations, she said, but the recent violations involving the mine’s ventilation system “are a red flag. It’s a signal that something is not right there, something is going wrong at that mine.”