PRUDHOE BAY, Alaska, Nov. 7 (UPI) -- Severe corrosion is rotting BP's pipelines in Alaska, an internal company report says.

The document, obtained by ProPublica, shows that as of Oct. 1, at least 148 BP pipelines on the Arctic North Slope got an "F-rank" from the company. BP workers said that means inspections have found more than 80 percent of the pipe wall is corroded and could rupture.


Most of those lines carry toxic or flammable substances, and many of the metal walls of the worst pipes are worn to within a few thousandths of an inch of bursting, risking explosions or spills.

Oil workers also say the fire- and gas-warning systems are weak, turbines that pump oil and gas through the system are aging, and some oil and waste holding tanks are near failure.

BP Alaska spokesman Steve Rinehart told ProPublica the company has "an aggressive and comprehensive pipeline inspection and maintenance program."

Photographs taken by employees in the Prudhoe Bay drilling field this summer show sagging and rusted pipelines.