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Valdez tank inspection debate continues Prince William Sound RCAC asks regulators to deny two-year delay of exam for huge oil storage tank at Alyeska Pipeline terminal Wesley Loy For Petroleum News
An oil industry monitoring group continues to press Alaska regulators to deny the operator of the Valdez tanker terminal permission to delay inspection of colossal crude storage tanks.
In a Feb. 29 letter to regulators, Mark Swanson, executive director of the Prince William Sound Regional Citizens’ Advisory Council, said his organization is “increasingly concerned with ... repeated attempts to extend tank inspection schedules.”
The letter to the Alaska Department of Environmental Conservation is the latest in a string of correspondence concerning the timelines for inspecting and cleaning storage tanks at the Alyeska Pipeline Service Co. oil terminal at Valdez.
Alyeska, based in Anchorage, operates the terminal and the 800-mile trans-Alaska oil pipeline on behalf of owner companies BP, ConocoPhillips, ExxonMobil, Koch Industries and Chevron.
Series of delays The citizens’ council is a congressionally sanctioned nonprofit organization that keeps watch over the Valdez Marine Terminal and associated tanker activity.
Swanson’s letter to DEC concerns Tank 10 at the terminal.
Tank 10 was last drained, cleaned and internally inspected in 2000, and was due for another such cleaning and inspection in 2010, a citizens’ council press release says. But the DEC granted Alyeska’s request to postpone the operation to 2012.
Now Alyeska wants to defer the next internal inspection until 2014.
“This action adds no measurable risk of a release or change to Alyeska’s ability to respond to an oil spill,” says a Jan. 31 letter from Alyeska’s director of regulatory affairs, Joseph Robertson, to DEC.
The citizens’ council previously complained about DEC granting Alyeska’s request to defer a scheduled internal inspection and cleaning of another tank, Tank 5, for two years until 2014.
‘Inside and out’ The Valdez Marine Terminal has 18 oil storage tanks, each with a capacity of 510,000 barrels. The tanks are about 63 feet high, with a diameter of 250 feet.
The tanks hold oil for loading onto tankers that dock at nearby piers.
Tank 10 was among several tanks Chicago Bridge & Iron Co. constructed in 1976, says Alyeska’s Jan. 31 letter to DEC. The tanks went into service in 1977, the year the pipeline started up.
The five-page Alyeska letter lays out the technical case for delaying the next internal inspection until 2014.
Tank 10’s original bottom was replaced with new steel floor plates in 2000, and a cathodic protection system was installed underneath to ward off corrosion, the letter says.
Three similarly overhauled CB&I-built tanks standing near Tank 10 — tanks 9, 11 and 12 — were drained down, cleaned and internally inspected in 2010 and 2011.
Results of these inspections turned up “minimal corrosion,” indicating that inspection of Tank 10 can be safely deferred until 2014, the Alyeska letter suggests.
The company says a revised American Petroleum Institute standard supports its request.
But the citizens’ council says the revised standard might conflict with Alaska laws and regulations. Swanson’s letter says “accepted engineering practice” calls for “thoroughly inspecting these tanks inside and out every 10 years,” not 14 years as Alyeska is requesting for Tank 10.
The citizens’ council also raises concern about the tank roofs and the extreme snow loads in Valdez.
Alyeska asserts the roofs are in good shape.
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