Recent Pipeline Issues
Alyeska Offers Explanation For Pipeline Shift At Atigun Pass
On June 20, 2000, Alyeska officials announced that the collapse of a gas pocket was to blame for the shift of the Trans-Alaska Pipeline at Atigin Pass. In mid-May, Alyeska discovered that a one-and-a-half mile section of the Trans-Alaska Pipeline had shifted as much as 6 inches on the south side of Atigun Pass in the Brooks Range. The shift apparently occurred on April 17, 2000, though Alyeska did not discover the problem until nearly a month later.
The incident, according to Alyeska, happened when a rushing flow of oil coming down the pass met a wall of vapor that was resting atop a pool of oil at the bottom. The vapor bubble condensed, then collapsed when it could not condense further. The resulting pressure wave was enough to shift the entire pipe.
Alyeska Senior Vice President Bill Howitt, ever one to appropriately spin the potentially catastrophic mishap, commented: "The good thing is we learned a lot from this incident" (Fairbanks Daily News-Miner, 6/21/00). The Alaska Forum sincerely hopes that Alyeska has learned something indeed.
The photos below are courtesy of the Joint Pipeline Office
Gouges Discovered in Trans-Alaska Pipeline
In late May 2000, Alyeska reported to the Joint Pipeline Office that they had discovered "gouges" in the outside of the Trans-Alaska Pipeline near Milepost 710. The pipe is buried at this location and was excavated when Alyeska's corrosion pig detected some wall loss. Instead of finding corrosion from the inside of the pipe, the wall loss, was the result of these exterior defects.
The gouges probably occurred during construction in the mid-1970's when some piece of heavy equipment collided with the pipe. Curiously, the gouges seem to have been leveled out with some kind of cement-like material. Clearly, the contractor laying this section of pipe found it easier to cover up the problem than report it and have it corrected.
The wall loss in some places at Milepost 710 approaches 80%. That is, instead of 1/2" thick steel, the pipe is barely 1/10" thick.
The Alaska Forum is compelled to wonder how many other contractor cover-ups are out there, undetected since the 1970's, that Alyeska has yet to discover.
The photos below are courtesy of the Joint Pipeline Office.
"Pipeline In Peril Report"
A Status Report on the Trans-Alaska Pipeline
prepared by Richard A. Fineberg, September 1996
for the Alaska Forum for Environmental Responsibility.