A blowout at an exploratory well near the coast of the Beaufort Sea underscores the threat to the pristine Arctic Ocean environment if offshore drilling is allowed by the Obama administration, environmental groups said Thursday.
No crude oil spilled onto the tundra and no workers were injured in the incident Wednesday, but an estimated 42,000 gallons of drilling mud was spit out of the well owned by Repsol E&P USA Inc. The blowout on the Colville River Delta, 18 miles northeast of the village of Nuiqsut, also expelled natural gas that could have ignited.
"What it shows is that there can be blowouts with exploratory wells hitting pockets of gas," said Pamela Miller of the Northern Alaska Environmental Center in Fairbanks.
Lois Epstein of The Wilderness Society in Anchorage said the well was drilled by an experienced company whose plans were reviewed by the Alaska Oil and Gas Conservation Commission.
"What this shows, and this is not the first time, is that drilling is a dirty and complicated business and that accidents happen, even to the best of companies, even with the best of oversight," she said. "What that tells me as someone who is working to find the right balance between drilling and protection is that you've got to recognize that certain areas, if you're going to allow drilling, there are going to be problems, and therefore the most sensitive areas need to be protected from drilling."
Water and small amounts of gas continued to flow from the well Thursday, said Cathy Foerster, one of three members of the Alaska Oil and Gas Conservation Commission. The commission oversees drilling for worker safety, environmental protection and petroleum conservation.
Workers must wait for gas to completely clear before starting machinery that can be used to regain control of the well, she said.
The cause of the incident has not been determined, Foerster said, but the commission will investigate.
The incident began when Repsol's contractor, Nabors Drilling, penetrated a shallow gas pocket at 2,535 feet. The release of pressure resulted in a gas kick that sent drilling mud spewing out of the hole.
Drilling mud, also called drilling fluid, is used to lubricate the drill shaft, cool the hole and carry cut rock to the surface. It's also used to apply downward pressure on gas or liquids that could flow upward.
"The drilling fluid that they had in the hole should have been adequate for what they were expecting to encounter," Foerster said. "We need to understand why it wasn't, and that will be part of our investigation."
Workers tried killing the well by pumping more fluid down the borehole. That mud also was blown out.
The well was equipped with a diverter, a required safety device that moved mud and natural gas about 75 feet from the well. The drilling crew shut down machinery to make sure the gas was not ignited.
Foerster said Repsol is new to Alaska but had hired local consultants for their drilling. The company, following requirements, had conducted a thorough shallow hazards survey to look for gas.
"Their survey did not identify the small lens of gas that they encountered," she said.
The commission has no indication that Repsol did anything wrong.
"We don't like it when this happens, but it's one of the known risks," Foerster said. "It's something we know might happen and we've engineered, not a solution to it, but a prevention of disaster. The diverter is what we have engineered to handle this kind of incident should it happen, and it does, so everything happened the way it was supposed to happen."
Foerster does not describe the incident as a blowout. There no burning rig, loss of life or oil spread over the tundra. A better description, she said, is a "loss of well control."
"That term is very accurate and it doesn't have any of the emotional terror attached to it that `blowout' does," Foerster said.
Repsol E&P USA Inc. is a subsidiary of Spain energy company Repsol-YPF. The company holds the second-most leases in the Chukchi Sea off Alaska's northwest coast, where Royal Dutch Shell PLC's U.S. unit hopes to drill exploratory wells this summer. Shell Oil Co. is awaiting federal approval of its spill response plan, which includes a "capping stack" that can be lowered onto a well and a flotilla of spill response vessels accompanying drill ships. Shell spokeswoman Kelly op de Weegh said there is no comparison to the preventative measure and contingency plans that Shell has in place for its offshore program.
Miller, of the Northern Environmental Center, said it was fortunate the Repsol drilling rig did not explode and that the incident took place on land during winter, when the rig can be reached by ice road.
"If you're 100 miles offshore in the Arctic Ocean, the logistic are just magnified enormously for response to the event itself, much less in the event of a major spill, in moving ice and water."
Epstein said it wouldn't be unheard of for a company to drill into a high-pressure oil reserve that it wasn't prepared for.
"That is what happened with Deepwater Horizon, so I don't think industry can say that's just not going to happen in the Arctic," she said.