Permafrost-Related Performance of the Trans Alaska Oil PipelineElden R. Johnson, PE Abstract The Trans Alaska Oil Pipeline System crosses 1287
km (800 mi) of Alaska, from the Prudhoe Bay oil field on the Beaufort
Sea (latitude 71°N) to the marine terminal at the ice-free port
of Valdez. Approximately 75% of the route consists of permafrost,
transecting the full range of conditions from cold, deep and continuous
in the north, discontinuous in the interior, and sporadic to frost-free
in the south. The pipeline has operated for over 30 years, transporting
nearly 2.5 billion cubic meters (16 billion barrels) of warm crude
oil in a harsh, technically problematic, and fragile arctic environment.
The lifetime operating reliability of the pipeline has been nearly
99%, with only 12 lifetime spills exceeding the 50-barrel definition.
This remarkable performance record attests to the functional, environmental
and economic success of the project. This paper describes permafrost-related
experiences and engineering lessons learned regarding the performance
of the pipeline. |
||