Pipeline at 40: Robots on patrol for corrosion

Published: Jul. 20, 2017 at 12:45 PM AKDT
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After its 800-mile journey across Alaska, oil that flows through the Trans Alaska Pipeline ends up at the Valdez Marine Terminal, which is a $1.4-billion dollar facility that was built on a site, blasted from the mountainside, above Valdez harbor, in the early 1970s.

“It was a substantial construction effort,” said Scott Hicks, director of operations and maintenance. “It's almost an engineering marvel in construction.”

The facility covers almost 1,000 acres. And there are 14 huge tanks currently in use, in order to store North Slope crude oil, before it's loaded onto tankers.

“The typical tank is 60 feet tall, 250-feet across, and they'll hold 550-thousand barrels,” said Weston Branshaw, the terminal operations manager.

Many of the pipes that move oil to and from the tanks are buried, and they have not been inspected, since they were welded together over 40 years ago.

Previously, inspection devices, called pigs, were unable to look inside, due to the steepness of the facility, which rises more than 600-feet above sea level.

Alyeska Pipeline is now engaged in an inspection program, using technology that was unavailable in years past. Now, the company uses robots, which can crawl through the pipes on mini tank treads and use cameras, lasers and ultrasound sensors to inspect the interior of the pipe.

“We can inspect 100 percent of the pipe for defects, corrosion, anomalies, dents (and) anything else we can find,” said Andrew Ellis of Diakont, the company that operates the robots.

The Valdez Marine Terminal has seen changes, during the pipeline’s first 40 years. Four storage tanks at the highest part of the terminal, were shut down in 2013 because of less oil flowing through the pipeline. The pipes that used to connect them to the rest of the terminal were cut and plugged.

The reduced oil flow has also lead to an unexpected problem; deep snow collecting on the roofs of the giant storage tanks. In years past, the oil remained warm enough to melt the snow, but the reduced flow rates in the pipeline give the oil time to cool down enough that it can’t warm the tanks enough to melt snow.

“In the winter of 2011 and 2012, we had over 130 people that were dedicated to snow removal” according to Hicks. “Up on top of the tanks, a crew of between 10 and 11 people would take almost a full week to fully move the snow off of one tank, so it just went from tank to tank.”

Hicks added “The tanks have solid roofs and they're almost an acre in size, and so it's like hand shoveling a parking lot of a major business in size, and we have 14 of them.”

One of the biggest changes at the Valdez Marine Terminal since the pipeline began operations is scheduled to take place in July, 2018 when a Louisiana-based company named Edison Chouest will take over tanker escort and spill response duties from Crowley, the company that has performed those services since the early 1990’s.

“Alyeska (Pipeline) is continuously reviewing all of our contracts and bidding them, so it just came up in the cycle” said Andres Morales, director of the Ship Escort/Response Vessel System, known as SERVS. “We bid it to see what else was out there and Edison Chouest had the best value for us going forward.”

SERVS was established after the Exxon Valdez oil spill in 1989, and the change to a new company is causing concern among environmentalists.

“I just don't think that somebody from Louisiana has the understanding of what goes on in terms of Prince William Sound and the difficulties” said Peg Tileston, co-found of Trustees for Alaska.

The Prince William Sound Regional Citizens’ Advisory Council, which was set up after the Exxon Valdez spill, wants to make sure the new company’s boats and crews are tested and fully trained before taking over escort and spill response.

“It's very important that they hear the concerns of the local people especially those who lived through the Exxon spill that know first-hand the damages that can happen should a spill occur” said Brooke Taylor, spokesperson for the RCAC.

Managers for Alyeska Pipeline and SERVS are confident the transition will be smooth. “They (Edison Chouest) have a great deal of experience in arctic and Antarctic and subarctic waters, a great deal in escort and ship docking” said Morales. “We're feeling very comfortable with them.

They bring a world of expertise to this operation.”

Many employees of the Valdez Marine Terminal feel they have a personal stake in making sure there is never a repeat of the Exxon Valdez spill.

Operations manager Weston Branshaw was raised in Cordova, a member of the third generation of a commercial fishing family. “There's a lot of communities and people in the sound and that's their livelihood”

Branshaw said. “That's how they make their living, feed their children, so, it's very important to us to make sure the oil doesn't hit the water.”

While there may be debate over who should escort tankers, there is one goal and mission shared by everyone in the area, and that’s to get the oil in and out of the pipeline’s Valdez terminal safely, and spill-free.

(Note: Edison Chouest company officials declined comment for this story)