Petroleum News

Chevron has repaired a corroded pipeline riser and placed its Anna platform in Alaska’s Cook Inlet back on production.

“We started shipping oil from the Anna on June 12,” company spokeswoman Roxanne Sinz told Petroleum News today via e-mail.

The Anna platform, southwest of the village of Tyonek, has averaged 1,030 barrels per day since the restart, Sinz said.

Shipping resumed after a “composite pipeline repair of the riser” was installed and the repair had “properly cured,” says a Chevron letter dated June 18 to the U.S. Pipeline and Hazardous Materials Safety Administration.

The letter was posted July 6 on a federal website.

The letter says PHMSA officials witnessed the repair and approved restarting operation of the pipeline.

The pipeline and riser carry production from the Anna platform to the neighboring Bruce platform.

From there, oil goes to the onshore Granite Point production facility.

The issue was a corrosion “feature” on the 12-inch riser, which is inside a leg of the Bruce platform.

Chevron had asked PHMSA for a special permit to waive compliance with pipeline safety regulations.

Corrosion has partially eaten through the riser wall, but Chevron asserted the remaining wall thickness was sufficient to handle the low operating pressures.

PHMSA, however, denied the special permit with an April 27 letter, and Chevron shut down production from Anna