When British Petroleum (BP) shut down a vital oil pipeline, the company blamed "unexpectedly severe corrosion" in transit pipes. Yet only five months ago, BP's aging pipeline created the largest-ever oil spill on Alaska’s North Slope.
Federal regulators blamed the spill on "internal corrosion" and said in some areas the walls of the pipes were so corroded they were almost paper-thin.
So critics and industry experts say the latest problem was hardly a surprise.
"I think this was predictable and preventable," says Phil Flynn, an energy analyst with Alaron Trading Corp.
In fact, allegations about BP's maintenance practices have been so persistent that a criminal investigation now is under way into whether BP has for years deliberately shortchanged maintenance and falsified records to cover it up.
The criminal probe was triggered by Chuck Hamel, a longtime nemesis of the oil companies and advocate for oil workers.
"They're playing the Russian roulette up there," he says.
Hamel says a dozen past and current BP employees came to him claiming they'd been told to cut back on a chemical put into the system to retard rust and corrosion, and to falsify records. A federal official confirms that many of these workers have also talked to the FBI.
"They were telling me that they were not properly injecting the corrosion inhibitors into the system," says Hamel.
Does he think it was deliberate?
"Absolutely," he says, "to save money."
This week, in announcing the shutdown, BP acknowledged that a key maintenance procedure to check for sludge — known as "pigging" — had not been performed in more than a decade.
Tuesday, in an interview with NBC News, a federal official in charge of pipeline safety charged that BP has been doing inadequate maintenance for 15 years.
"Frankly, we would have expected a higher level of care from a company like BP on lines like this," says Thomas J. Barrett with the Department of Transportation's Office of Pipeline Safety.
"What disappointed me was their failure to maintain these lines to an accepted industry level of care," Barrett says.
Tuesday night, BP would not comment on the criminal investigation, but insists that its maintenance program was adequate. The company says it has changed its inspection program to spot problems earlier.