A spill from the trans-Alaska pipleline totaled about 5,000 barrels, making it the third-largest spill from the 800-mile pipeline.  Alyeska Pipeline Services Co. kept the pipeline shutdown for 3 days after discovering the spill at Pump Station 9 near Delta Junction.  Alyeska was testing it fire command system when power at the pump station failed.  Power was switched from the electrical grid to a battery system.  The pipeline has relief valves that open to prevent pressure from increasing inside.  They opened and oil flowed into a partially filled tank.  A control circuit in the battery system failed to close the relief valve and oil filled the tank and overflowed into the secondary containment area.  The containment area is lined with an impermeable liner.  No oil escaped from the area. The pipeline reopened on May 28, 2010.  The pipeline was shut down for 79 hours.

About 5,000 barrels of oil spilled from the trans-Alaska pipeline.  The pipeline was shut down for 79 hours. The disruption resulted in $45 million/day in North Slope production and about $13 million in state revenue. There is a crew of about 125 people on site to manage the clean up and restart.