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Corrosion risk cited at Valdez terminal Dr. Rust says piping damage discovered in 2012 was repaired before any oil leaked into port; Alyeska defends anti-corrosion efforts Wesley Loy For Petroleum News
A consultant is recommending improved piping inspections to safeguard against corrosion and possible oil spills at the Valdez tanker terminal.
Modifications are needed “as soon as possible” to enable the use of smart pigs in the terminal’s crude oil piping, the consultant said. Smart pigs are tools that slide through pipelines to test for corrosion or other problems.
The consultant further said Alyeska Pipeline Service Co., the terminal operator, “has not embraced the best management practice” of annual inspections of piping that extends over water.
The consultant’s report contains photos and details of Alyeska’s discovery, in summer 2012, of extensive corrosion in piping on the two active berths where tankers load crude. The berths extend out into the waters of Port Valdez.
The corrosion was underneath insulation on the piping, at welds lacking a protective coating. Repairs were made before any leaks occurred, the report said.
“If the corrosion had not been discovered in time, it could have led to crude oil releases into Port Valdez,” the report said.
An Alyeska spokeswoman, Michelle Egan, told Petroleum News the company takes issue with some of the consultant’s conclusions.
Dr. Rust Inc. The Valdez Marine Terminal anchors the southern end of the 800-mile trans-Alaska oil pipeline. It is a sprawling complex of enormous oil storage tanks and piers where tankers tie up for loading. The terminal includes extensive piping, much of which is either buried or shrouded in insulation, making inspection difficult.
As in any aging industrial facility, corrosion is a constant threat at the Valdez terminal. North Slope crude has been flowing into the terminal since 1977.
The Prince William Sound Regional Citizens’ Advisory Council, which watches over terminal and tanker operations, hired the corrosion and engineering consulting firm Dr. Rust Inc., of Cape Canaveral, Fla., to conduct a corrosion survey of the terminal.
The consultant delivered a final report dated Dec. 20 to the council.
The Dr. Rust team, led by Bob Heidersbach, reviewed Alyeska records and procedures and paid a three-day visit to the terminal Aug. 6-8.
The report said no attempt was made at a detailed corrosion inspection of the terminal.
“We did, however, note corrosion whenever we saw it,” the report said.
The consultant also noted that the trans-Alaska pipeline and Valdez Marine Terminal “were designed and built at a time when the petroleum industry was not fully aware of the problems associated with” corrosion under insulation.
Jacket damage A big focus for the consultant was the insulated pipes suspended along the causeways to the tanker berths. The report includes several photos showing holes, tears or other defects in the metal weather jacketing on the pipes. Such openings can allow water to enter, leading to corrosion, the report said.
Some gouges seen in the jacketing probably happened during snow removal efforts in the winter of 2011-12, the report said.
Although damaged areas were readily visible, “no actions seem to have been taken or planned to assess whether corrosion has resulted from the defects in the external weather jacketing on the over-water piping” leading to the tanker berths, the report said.
The report noted that most piping at the terminal, even piping over water, isn’t subject to federal inspection requirements applicable to the main 48-inch oil pipeline coming into the terminal.
The consultant suggested even worse corrosion than that found and repaired in 2012 might be lurking in the berth piping.
“The entire system needs to be inspected as soon as possible,” the report said.
The report recommends that until smart pigging capability is installed, the terminal operator should “emphasize inspection of all above-water piping systems to determine if corrosion under insulation has occurred.”
‘Misleading conclusions’ In a Dec. 20 letter to the citizens’ council, Alyeska’s Valdez operations director, Scott Hicks, said company staff spent substantial time providing information and documents to Dr. Rust.
Yet the consulting firm’s report contains “misleading conclusions,” Hicks wrote.
Alyeska’s inspection plan does include annual inspections of piping over water, he said. Alyeska has completed more than 450 integrity inspections of piping on the two tanker berths, dating back to 1992, Hicks wrote.
And Alyeska’s piping integrity program “does not differentiate between regulated and non-regulated piping,” he said.
Egan, the Alyeska spokeswoman, said Alyeska is looking at options for better inspection of terminal piping. Ideas include pigging or bringing some buried pipes above ground to allow for ultrasonic testing, which can determine pipeline wall thickness.
These considerations began before Dr. Rust came on the scene, Egan said.
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