Corrosion protection system for terminal’s crude oil pipes in good shape overall

Keith Boswell from National Pipeline Services observes cathodic protection system equipment at the Valdez Marine Terminal in 2019.

A recent study of operations and maintenance of Alyeska’s cathodic protection system found that the program was “very good;” however improvements are still needed.

National Pipeline Services, a consulting company that specializes in cathodic protections, conducted the study for the Council. They looked specifically at the systems that prevent corrosion in the metal piping that carries crude oil through the terminal to the large oil storage tanks.

The researchers based their report on a review of documents, procedures, testing, and results from previous inspections of those systems.

The final report summarized the systems currently in use at the terminal, as well as Alyeska’s methods for monitoring and testing the systems.

The researchers concluded that overall, it appears Alyeska has a “very good corrosion and cathodic protection program.” The procedures for operating and monitoring the system are adequate and within standard industry practices and Federal guided requirements.

The report also noted that certain improvements could further reduce the risk of a crude oil spill, such as ensuring data collection procedures are adequately implemented. Data used to ensure that the crude oil piping’s cathodic protection system is operating effectively does not appear to have been collected properly.

The researchers commended Alyeska on their use of remote monitoring systems, which continuously monitor and evaluate the systems. They added that Alyeska’s annual reporting for integrity management is exceptional and well documented.

Report:

Review of Cathodic Protection Systems at the Valdez Marine Terminal (1.9 MB)

Review of maintenance records finds improvements needed for oil storage tank

Oil spill unlikely as long as planned repairs are not delayed further

Photo of Tank 8, which is one of the large crude oil storage tanks at the terminal. This tank is 63 feet tall, 250 feet in diameter, and can hold up to 21,420,000 gallons of crude oil.
Tank 8, seen here being cleaned in preparation for an internal inspection, is one of the large crude oil storage tanks at the terminal. This tank is 63 feet tall, 250 feet in diameter, and can hold up to 21,420,000 gallons of crude oil. Photo by Austin Love.

Last year, COVID-19 delayed planned repairs to one of the large crude oil storage tanks at the Valdez Marine Terminal. Alyeska rescheduled those repairs for 2023. A recent Council study found that, as long as these repairs are not delayed any longer than 2023, a spill is unlikely.

Taku Engineering, an engineering firm with expertise in tank and piping inspections, assessing and controlling corrosion, and cathodic protection conducted the tank inspection review for the Council. Taku’s engineers analyzed Alyeska’s documentation of inspections and maintenance for Tank 8 located within the East Tank Farm at the Valdez Marine Terminal.

2019 inspection raised concerns

After some concerning findings during a 2019 inspection of the inside of Tank 8, Alyeska planned to replace the tank floor and cathodic protection system. The repairs were scheduled for 2020. However, the COVID-19 pandemic delayed those major repairs. The Alaska Department of Environmental Conservation extended the deadline for completion to 2023. The tank will then be removed from service and repairs made.

Council conducted study to minimize risk of oil spills

Taku’s report concluded that the immediate risk of a leak from Tank 8 between now and 2023 is low. The engineers made several recommendations that would help ensure that a spill remains unlikely. They found that an unmaintained seal around the perimeter of the tank allowed rain and snow melt to migrate and accumulate under the tank’s floor. Under certain circumstances, this could lead to damage. Taku recommended that Alyeska maintain the seal so water cannot cause these problems.

Taku also found that some of the cathodic protection system testing data was inadequate. That data is used to ensure that the system is operating effectively, safeguarding the tank’s floor from corrosion.

Report

Details are available in the final report: 

 

New buoys now streaming weather conditions from Port Valdez

Photo of new buoy deployed in 2019.

Two new buoys are now in place and broadcasting weather conditions in the vicinity of the Valdez Marine Terminal.

Photo of new buoy deployed in 2019.

The buoys collect weather data such as temperature, wind speed, wind direction, and barometric pressure, as well as oceanographic information like surface current direction and speed, wave heights, and water temperature. This data will help improve understanding of the meteorological and physical oceanographic environment in Port Valdez.

Weather conditions throughout Prince William Sound

Terminal buoy result of cooperative partnership

The buoy closest to the terminal (pictured above) is the result of a partnership between the Council, the Prince William Sound Science Center, Alyeska Pipeline Service Company, the City of Valdez, and Valdez Fisheries Development Association.

“Partnerships like these result in collaborative science, which is the best base for providing answers to challenging questions related to planning an effective oil spill response,” said Donna Schantz, Executive Director for the Council. “The Council has long advocated for this kind of data collection at the terminal and believe the information generated will contribute to best practices for prevention and response.”

The partnership is a result of an agreement reached between the Council, the City of Valdez, Prince William Sound Aquaculture Corporation, Valdez Fisheries Development Association, Alyeska Pipeline Service Company, and the Alaska Department of Environmental Conservation regarding protections in the Valdez Marine Terminal contingency plan for two nearby areas that are particularly sensitive to spilled oil, the Solomon Gulch fish hatchery and a salt marsh known as the Valdez Duck Flats.

In 1994, the tanker Eastern Lion spilled 8,400 gallons of North Slope crude oil into Port Valdez. Oil reached the Duck Flats and hatchery before protective boom was in place.

After that spill, changes were made to the Valdez Marine Terminal contingency plan to ensure that protections were deployed quickly. A rapid-decision tool, called a “matrix,” was created to help responders assess when to deploy protective boom to the Solomon Gulch Hatchery and Valdez Duck Flats during the critical early hours of a response. In 2017, the matrix was modified, and the Council, the City of Valdez, Valdez Fisheries Development Association, and Prince William Sound Aquaculture Corporation appealed that decision.

Earlier this year, the parties agreed to stay the appeal in lieu of a collaborative workgroup process. The workgroup’s goal is to reach consensus on how to ensure the protection of the Solomon Gulch Hatchery and Valdez Duck Flats. The buoys will provide scientific data to help the workgroup better understand how spilled oil will move in Port Valdez. This knowledge will help determine the timing for deploying protective boom.

Second buoy monitors Valdez Duck Flats

A second buoy has been deployed near the Valdez Duck Flats to monitor conditions in that location. The second buoy has been made possible by partnerships with Prince William Sound Science Center, the City of Valdez, and Valdez Fisheries Development Association.

Map

The map shows the locations of the two sensitive areas of concern, as well as the location of the new buoys. The hatchery is a little over two miles from the terminal, and the flats are approximately four miles.

Piping inspections near completion

By Austin Love
Council Project Manager

For the first time since the facility’s construction was completed in 1977, a majority of the large diameter crude oil piping at Alyeska’s Valdez Marine Terminal is undergoing a comprehensive inspection, both externally and internally. The inspections of these 36 and 48 inch diameter pipes began in 2016, and will be completed by the end of 2018.

Alyeska can use the data from these inspections to evaluate the current, complete condition of the large diameter piping used to move Alaska North Slope Crude onto tanker ships at the terminal.

A tremendous amount of work by Alyeska and their contractors is making these inspections possible:

  • Concrete foundations had to be reinforced to accommodate loading stresses associated with the inspections;
  • Piping inspection tool access and retrieval points had to be created at multiple locations;
  • Sharp bends and large valves had to be removed from certain piping sections to allow for the passage of inspection equipment;
  • The piping has to be cleaned of accumulated wax and debris after 40 years of use; and
  • With the exception of a few necessary, planned pipeline shutdowns, most of this work was done while crude oil was still flowing through the pipeline and tank ships were still loading.

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