In the Field
Weather impacts tanker loading and pipeline flow

In late November, Alyeska had to suspend tanker loading activity periodically at the Valdez Marine Terminal (VMT) due to high wind and wave conditions in Port Valdez. Company protocol calls for Alyeska to suspend transfer operations when the waves begin to breach the oil spill containment boom that surrounds tankers when at berth.

The weather conditions, combined with high crude oil inventory levels in the storage tanks at the VMT, also led to temporary shutdowns of the pipeline. During the weather delays, the North Slope production into the system was restricted at Pump Station 1 to slow down the flow of oil into the terminal. During the course of this extended event, Alyeska operated in what is called a “cyclic” mode meaning the Operations Control Center ran the pipeline for about six hours and then shut down for six hours.

“This action helped us keep the oil moving in a way that balanced the slope proration, the inventory levels in Valdez and our operational needs,” said Mike Joynor, Vice President, Oil Movements. “Weather challenges aren’t unique to Southcentral Alaska, so we were able to identify and prepare for this high inventory situation several days beforehand to help us manage through this event. I really want to recognize the TAPS employees that worked around the clock to find and execute an acceptable solution that met our safety standards.”

There are 14 oil storage tanks currently in service, each of which can hold more than 500,000 barrels of oil. Four additional tanks are currently out of service while Alyeska evaluates future storage capacity as a result of the decline in throughput production from the North Slope.