Number of pipeline spills in Cook Inlet at issue

Kristen Nelson

Cook Inlet Keeper said Jan. 10 that the number of pipeline-related in spills in Cook Inlet is increasing, and now averages one a week.

This is a number industry hotly disputes.

“The Cook Inlet pipelines have a much better record — safety record — than the national average for hydrocarbon pipelines,” Martin Morell, Unocal Alaska’s operations manager, said Jan. 10 at a Cook Inlet pipeline forum in Soldotna.

The U.S. Department of Transportation has had a classification system in place for reporting pipeline leakage since 1986.

“Since that current record-keeping system has been in place,” Morell said, “Cook Inlet pipelines have about a 4 times better safety record than the national average.”

He credited this record to two things: the use of very heavy pipe in Cook Inlet and “the strong preventive program that pipeline operators have used to protect these lines.”

There have been leaks, he said, and the most dramatic leaks have been caused by external damage. In the early 1990s a piece of heavy earth-moving equipment punctured one of the pipelines at a beach crossing, “and even though this was the largest oil spill in the history of Cook Inlet pipelines, that oil was all contained and cleaned up at the leak site.” None of that oil actually got into the inlet, he said.

“Since that time the lessons learned from that incident have been applied in damage prevention and pipeline survey programs which cover all the pipelines,” Morell said.

External corrosion on risers — where pipelines rise up to meet the platform — have cases small spills were rust penetrated the pipeline.

“Since that time, all the pipelines are more frequently inspected and are very well protected in these tidal zones,” Morell said.

Since DOT record-keeping began in 1986, Morell said, the six pipeline accidents that occurred have been very well studied.

“And the lessons learned from those have been applied to the various maintenance and pipeline integrity programs across the Cook Inlet.”

Unocal spokeswoman Roxanne Sinz told PNA that of the six leaks in active Cook Inlet marine crude oil pipelines, about half occurred more than 10 years ago.

“That safety record is about 4 times better than the national average for liquid hydrocarbon pipelines.”