Backpressure System Repairs Continue

Alyeska Pipeline has drained and inspected the piping for the backpressure control system at the Valdez Marine Terminal. The inspection revealed that pieces of a pipeline cleaning pig are located in the backpressure piping. The backpressure control system was taken off-line for inspection and repair last Monday because a restriction in the piping or valves was causing a higher than normal backpressure. The day before the system was taken off-line, pieces of a pipeline cleaning pig had arrived at the Marine Terminal. The transmitter from the pig was detected through an audio signal in the backpressure piping last week.

A work plan has been developed to dismantle, clean, repair, and reassemble the backpressure piping. Work to inspect and repair the backpressure piping will continue on a 24-hour per day schedule. Work is expected to be complete in two to three weeks. The system was installed in 1997 to eliminate vibrations in the pipeline on the south slope of Thompson Pass. The vibrations experienced while the backpressure system is offline do not create a risk to pipeline integrity. The residents of the neighborhood near the pipeline in this area have been notified of the situation and the repair schedule