The Prudhoe Bay oil field spill on Alaska's North Slope is seen on Monday, March 13, 2006. Cleaning up the spill estimated at up to 267,000 gallons in the Prudhoe Bay oil field has been slow going because workers are having to take frequent breaks to protect themselves against extreme conditions. (AP Photo/Rick Bowmer)

The publicity caused by the leak in the the 30-year-old pipeline could seriously damage BP's image, which has been carefully crafted to show it as a company concerned about the environment. Unlike other major oil companies, BP boasts that it is fully signed up to the dangers of global warming and it makes a conspicuous effort to flaunt its green credentials, tackling local environmental problems and erecting wind turbines above its petrol stations.

The first indication of the spill came in early March, when an oily patch was discovered near the elevated oil transmission pipeline, but the full scale of the accident is only becoming clear with time. Environmentalists who vociferously objected to the construction of the BP pipeline may now see their worst fears realised.

Clean-up crews have removed more than 190,000 litres of crude oil and melted snow off the frozen tundra but reports indicate that the leak is the second largest crude oil spill in Alaska - second only to the 1989 Exxon Valdez disaster.

The oil gushed from the pipeline at a spot where it dips to ground level to allow caribou to cross, and has led industry critics and environmental groups to question whether BP is saving money on maintaining its network of wells, pumps and pipelines crisscrossing the tundra - a complaint the company vigorously denies.

As oil is increasingly transported through environmentally sensitive areas by pipeline, the dangers posed by poorly maintained rotting pipes has become increasingly clear.

Exploration Alaska, the BP subsidiary that operates the pipeline from which more than 910,000 litres of oil has leaked, has recently been fined more than $1.2m (£635,000) for its poor environmental safety record.

The company has now been told it cannot restart pumping oil until it the entire pipeline has been inspected and repaired. Employees claim that they repeatedly warned that money-saving cutbacks in routine maintenance and inspection had dramatically increased the chances of accidents or spills.

"For years we've been warning the company about cutting back on maintenance," Marc Kovac, a union official told the New York Times. "We know that this could have been prevented."

In the interview, Marc Kovac, an official of the United Steelworkers union which represents workers at the BP facility, said he had seen little change in BP Exploration Alaska's approach despite the warnings.

In an e-mail to a company lawyer in June 2004, Mr Kovac forwarded a collection of his earlier complaints to management. One of these, dated 28 February 2003, concerned "corrosion monitoring staffing levels". It began, "The corrosion monitoring crew will soon be reduced to six staff down from eight."

It added: "With the present staff, the crew is currently one month behind. The backlog is expected to increase with a further reduction in manpower."

Daren Beaudo, a company spokesman, said: "Whenever employees raise concerns about our operations we address them. When we inspected the line in September 2005, points of manageable corrosion were evident and all were within standards of operations integrity.

"Something happened to the corrosion rates in that line between September 2005 and the time of the spill that we don't yet fully understand."

© 2006 Independent News and Media Limited

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