Environment

Consultant doubts capabilities of tugs taking over tanker escort in Prince William Sound

A marine engineer hired by the oil-spill watchdog group for Prince William Sound has identified "fairly significant deficiencies" in plans for two sets of tanker-escort tugs being built by Edison Chouest, the impending oil-spill prevention and response contractor at the Valdez Marine Terminal.

"We don't see that enough work has been done in either design to enable them to be declared fit for purpose," said Robert Allan, executive chair of Robert Allan Ltd., a longtime Canadian naval architectural firm based in Vancouver, British Columbia.

Allan said he had concerns related to the tugs' overall performance design, particularly their ability to safely tow the massive tankers and handle Alaska's powerful waves and icy conditions.

Allan provided the statements to the Prince William Sound Regional Citizens' Advisory Council Jan.19, summarizing a draft report the council has not yet publicly released.

In July 2018, Edison Chouest will take over the tanker-escort duties from Florida-based Crowley Marine, which had provided the service under contract with Alyeska Pipeline Service Co. since 1990, the year after the Exxon Valdez oil spill occurred. RCAC was created by post-spill federal regulations.

Edison Chouest was one of the companies faulted by the federal government for errors leading to the grounding of Shell's Kulluk drilling rig off Kodiak in late 2012. The U.S. Coast Guard in 2014 said design flaws in Edison Chouest's giant tug, the Aiviq, contributed to the failure of its engines while it towed the Kulluk.

Louisiana-based Edison Chouest is both a shipbuilder and tug and support-ship operator.

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The Aiviq won't be used in the tanker-escort service and related work for Alyeska, Edison Chouest has said. Online ship tracking reports show the $200 million icebreaker and support ship — built in 2012 — has been laid up in Tampa Bay, Florida since September, out of service.

Last summer the Aiviq was in waters north of Alaska, helping Shell haul away dozens of giant anchors and related equipment plucked from the seafloor, remnants of the oil giant's failed exploration efforts in the Chuckchi and Beaufort seas.

The company is currently building five escort tugs and four support tugs in Lousiana and Mississippi to meet the terms of the new contract with Alyeska, officials said.

Linda Leary, with Fairweather, an Edison Chouest company in Alaska, referred questions to Alyeska.

Donna Schantz, RCAC executive director, said information for Allan's review began arriving in late October, provided by Alyeska. It is possible some flaws Allan highlighted may have been addressed.

Still, Allan's findings generate several concerns, she said.

"One of our biggest concerns now is that these vessels are already being built, so it's not clear how much we'll be able to influence the designs of those tugs before it's too late or too costly to make any design changes," she said.

Alyeska has said it is taking the issues raised in the draft report seriously, and will address them with Edison Chouest and Damen, its Netherlands-based tug designer, said Schantz.

Alyeska is reviewing Allan's report, spokesperson Michelle Egan said on Wednesday.

Egan said the report was written using "preliminary information" about vessel design. She said some design details have not been provided by Damen because they contain proprietary information, she said.

"As part of the construction process, improvements to the vessels are ongoing," Egan said in an emailed statement.

She said "significant expertise" has gone into the design, and several groups will ensure the vessels' readiness, including the U.S. Coast Guard, the American Bureau of Shipping and the Alaska Department of Environmental Conservation.

"They are a solid improvement over the current fleet and will be among the most high-performing tugs in the world," she said.

But in his RCAC presentation, Allan said he's concerned the new tugs will be less capable than Crowley's fleet.

"If you can't be assured these vessels will provide the same level of service as you have today, there is a serious shortcoming," he said.

Early on in his report, Allan told the council he's a shipbuilder who competes with Damen, and some people might mistakenly characterize his views as "petty jealousies."

"We have looked at this as professional engineers," he said.

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Allan outlined a long list of concerns, including that to his knowledge, the large escort tugs have not undergone model-testing to determine their capabilities operating in high waves and bad weather. That's a "very serious omission," he said.

Another worry is the foredeck design on the escort tugs. A space like a "swimming pool" could fill with water when the ship hits heavy seas, creating a danger as the tug tries to ride up waves.

If "tons of water" have not drained through a series of freeing ports the "pool"  could be blocked with ice or snow.

"Some things perhaps could be done to enlarge the freeing port area," he said.

He said the addition of bow thrusters to aid maneuverability could help the tugs during ship-handling duties. A portion of the bow is bluff — broad and flat — a shape that could cause the tug to lose speed in big waves, he added.

"When you stick the bow of that boat into a big sea, it will be like hitting a brick wall," he said.

As for the smaller support tugs, Allan said he was concerned Edison Chouest tugs wouldn't be tested on a tether with smaller tankers until after the transition from Crowley.

"My jaw sort of hit ground when I read that," Allan said. "It seems incredible to me that one would go ahead and build a fleet of these boats without being assured that they are able to conduct the task that is asked of them."

Alex DeMarban

Alex DeMarban is a longtime Alaska journalist who covers business, the oil and gas industries and general assignments. Reach him at 907-257-4317 or alex@adn.com.

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