An underwater gas pipeline in Alaska that had been leaking gas for almost five months has finally been repaired.
The 8-inch diameter pipeline, which supplies gas for power to four Hilcorp Alaska, LLC production platforms, was found leaking on Feb. 7 when a helicopter crew spotted gas bubbling near it.
An analysis of the flow found that the pipeline likely started to leak in mid-December. Hilcorp said floating ice and other weather conditions made it too dangerous for divers to reach the leak sooner.
Dive crews began working on repairing the leak on April 8 and finished Thursday night.
“Now that the leak has been stopped, over the next several days, as weather permits, further inspection and stabilization of both the oil and gas pipelines in Middle Ground Shoal will be completed,” Hilcorp said, as reported by KTUU. “Neither pipeline will be returned to regular service until Hilcorp, along with state and federal regulators, agree it is safe to do so.”
The leak spewed hundreds of thousands of cubic feet of processed natural gas into Alaska’s Cook Inlet, which is home to endangered beluga whales and other marine mammals. It leaked twice in 2014.
Environmental groups are concerned about both the short and long-term effects of the leak, and many are calling for a risk assessment of the area, given the extensive network of energy infrastructure in the inlet.
“It’s scary to think about how decayed some of the offshore pipelines littering Cook Inlet may be,” Kristen Monsell, an attorney for the Center for Biological Diversity, said in a statement. “These old, vulnerable pipelines pose a toxic threat to the people and wildlife of Cook Inlet.”
Hilcorp is also looking into two other potential Cook Inlet leaks.