Pipeline corrosion upgrade planned

The operator of the trans-Alaska pipeline system, or TAPS, is planning a significant anti-corrosion project near the line’s northern end.

The project is slated for milepost 25 along the 800-mile oil pipeline.

Alyeska Pipeline Service Co., the Anchorage-based energy company consortium that runs the line, has applied to the State Pipeline Coordinator’s Office for an amendment to the TAPS right-of-way lease.

The amendment would add four acres to accommodate construction and new equipment for the cathodic protection project.

Cathodic protection is a widely used industry method for preventing corrosion. It involves the use of “sacrificial anodes” and electrical current to reduce the corrosion rate of a metallic structure.

A recent public notice said Alyeska plans construction activity along the Dalton Highway and a TAPS access road.

“A gravel pad will be constructed adjacent to the access road and a generator module will be installed to support a cathodic protection system in the area,” the notice said. Fuel for the generator will come from the nearby TAPS fuel gas line.

Alyeska spokeswoman Michelle Egan emailed Petroleum News some project background:

“All pipeline cathodic protection anode beds have a finite life. Anodes are sacrificial materials that deplete and require replacement after a period of time. The Cathodic Protection upgrade at MP 25 is a new cathodic protection anode bed being installed as part of our Cathodic Protection program to assure continuous supply of cathodic protection to protect the pipeline from external corrosion.”

The project, Egan added, is not the result of a regulatory action or any particular corrosion problem at milepost 25.

“The installation is part of our program to replace or supplement existing anode beds before cathodic protection in a particular area is no longer effective,” Egan wrote.

The cost to complete the project is expected to be under $5 million, she said.

—Wesley Loy