SeaRiver Marine Inc., Exxon's marine affiliate in the United States, signed an agreement with Aker Philadelphia Shipyard for the construction of two oil tankers valued at $400 million.
Each vessel would be designed to carry crude oil from the North Slope region of Alaska to the western coast of the United States.
"This project is a reminder of the importance of America's energy industry during the current challenging economic times," Andrew Swiger, Exxon Mobil senior vice president, said.
Each vessel would have a capacity of 730,000 barrels of crude oil. They're expected to be delivered in 2014.
A low-flow impact study produced by Alyeska Pipeline Co. in June found the Trans Alaska Pipeline has an expected service life of 10 years given anticipated declines in oil flows from the state.
The report from the pipeline manager suggested the pipeline can operate with a daily capacity of 350,000 barrels per day but anything less may be unpractical.