BP, which could face criminal charges over an oil spill in Alaska, came under further pressure yesterday as it was criticised by US federal regulators for failing to maintain its pipelines there properly.

The US Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMSA) has for the past six months conducted tests on “transit lines” across America owned by BP and its competitors. Its study showed that BP’s competitors had all well maintained their transit lines, which are currently unregulated, and there was little difference between them and the maintenance programmes used for regulated pipelines.

BP, however, fell short of standard industry practices in keeping its transit lines well maintained, the PHMSA said.

“Other operators kept their transit lines up to par and it is now evident from the data we gathered that BP did not,” a PHMSA spokesman said.

The transit lines are used for carrying a type of crude that was not thought to be particularly corrosive. Because of this, federal regulators do not currently require mandatory cleaning or checking of all types of transit lines. BP experienced two major leaks because of corrosion in its transit lines at Prudhoe Bay in Alaska. The first, in March, left 267,000 gallons of crude on the arctic tundra. A second leak, in August, led to the partial shutdown of the oilfield.

The PHMSA is now proposing a new rule that would require oil companies to maintain their transit lines properly.

The US Environmental Protection Agency is already investigating allegations that BP was negligent in maintenance of its Prudhoe Bay oilfield and that BP manipulated data to avoid replacing corroded pipelines there. Alaska’s attorney-general has ordered the company to retain documents related to corrosion.

The oil company has insisted that the discovery of corrosion in the transit lines was a shock because the oil carried by the pipeline was thought to be safe, and that its maintenance and monitoring of the pipeline was in line with industry practices.

Thomas Barrett, PHMSA administrator, said yesterday: “Quite frankly, the type of problem you have seen at Prudhoe Bay with BP on these low- stress lines, we have not seen replicated elsewhere in the country.”

Mr Barrett added that the problems at Prudhoe Bay provided evidence that BP had not exercised the standard of care usually seen in the industry.

BP did not return calls seeking comment yesterday.

MOUNTING WOES

• Monday: Lord Browne of Madingley, chief executive of BP, is ordered by a Texas court to testify in a lawsuit over an accident last year at a local refinery that killed 15 people and injured a further 170
  
• Tuesday: BP is ordered by the Commodity Futures Trading Commission, the US regulator, to give evidence over possible insider trading in the world crude oil price
  
• Next week: BP executives are being summoned before the US Congress to explain why pipeline problems forced the Prudhoe Bay shutdown

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