Mt. Redoubt, March 30, 2009. Heather Bleick; AVO/USGS
Following up on Monday’s discussion of volcano monitoring, Mt. Redoubt and the “wisdom of storing 6 million gallons of crude near an active volcano” we begin with a story from the Anchorage Daily News, February 2 — a week after rumblings were detected but more than six week prior to the latest round of eruptions:
When Mount Redoubt erupted 20 years ago, massive floods and raining pumice raised immediate alarms over the Drift River Oil Terminal, with its storage tanks of crude oil sitting at the foot of the volcano.
After several weeks of growing explosions, a big blast hit the lava dome, oil workers abandoned the scene by helicopter and the oil terminal was swept by a flood that turned the Drift River, briefly, into the largest river in North America.
Now Redoubt is restless again. Strong seismic tremors came and went Friday, as scientists said an eruption appeared still to be building.
So what’s the situation at Drift River this time?
Sorry. Nobody will say.
Citing new homeland security rules, a spokeswoman for Chevron refused to say how much oil is normally stored at Drift River these days, how much is currently on hand and whether there are plans to summon extra tankers and drain the tanks.
“That’s not public information,” said Chevron’s Roxanne Sinz. “We can’t release any numbers.”
State and federal oil spill officials will go a bit further. They say the storage at Drift River is being reduced this week. But they won’t say by how much.
“All I know is that the operators are keeping their levels down,” said Dianne Munson with the state Department of Environmental Conservation. She said the terminal has seven 270,000-barrel tanks.
Let’s break this down into bite-sized pieces.
Alaska is no stranger to oil spills. Last week, March 24 marked the 20th anniversary of the Exxon Valdez oil spill, one of the largest human-initiated environmental disasters ever to occur at sea. Nearly 11 million gallons of crude spilled into Prince William Sound, eventually covering 11,000 square miles of ocean.
Twenty years later, what have we learned?
The Drift River Oil Terminal has seven 270,000-barrel tanks. At 42 gallons per barrel, that’s a maximum capacity of 79,380,000 gallons. Obviously, the facility isn’t filled to capacity, but since Chevron won’t release any numbers, Alaskans can only guess that at any point the amount of oil at Drift River is somewhere between zero and 7 times the amount spilled by the Exxon Valdez.
Fast forward to March 27, 2009, three days after Mt. Redoubt began erupting. Evidently, the danger posed by sitting at the base of an active volcano has now been determined to be greater than the threat of terrorists. We’ve learned that three of the tanks have been decommissioned due to declining production at the Cook Inlet fields and two others are empty but on standby.
March 26/27, the Anchorage Daily News:
An eruption of Redoubt volcano Thursday morning triggered a flood of mud-choked water in the Drift River, but officials were at a loss to say whether it passed harmlessly by the oil facility near the mouth of the river or penetrated the protective dike there.
Rod Ficken, vice president of Cook Inlet Pipeline Co., said remote monitoring equipment on two tanks that each contain 3 million gallons of crude oil showed no change in their level, strong evidence that they remain intact.
But until observers can fly over the Drift River oil terminal and report back, no one will know how high the river reached and whether water and mud got into the tank farm, Ficken said. The facility has no remote video or flood sensing equipment, he said.
The terminal was evacuated Monday morning early in the series of eruptions that have periodically swollen the river and threatened the facility.
An eruption-triggered flood early Monday safely swept past the oil storage area, though some muddy water appeared to have lapped over a protective dike. A deposit of deep mud emerged on the nearby airstrip when the river receded.
Ficken said the engineer who designed the dike during Redoubt’s last eruption cycle in 1989-1990, Jim Aldrich, paid a visit to the site Thursday morning by helicopter. He and 10 others had to abandon the area quickly around 9:30 a.m. when the eruption started and the aviation safety code went from orange to red, Ficken said, but Aldrich was satisfied that Monday’s flood didn’t damage the concrete-clad earthen dike.
So, it turns out there are 6 million gallons accounted for in two tanks –Â still more than half that spilled by the Exxon Valdez. There’s no video or flood sensing equipment and the facility has been evacuated, but those 6 million gallons? Apparently, they’re going to stay:
Earlier this week, the environmental organization Cook Inletkeeper said the two operational tanks should be immediately drained to avoid a catastrophic spill if floodwaters breached the dike.
But Ficken, the pipeline company official, said it’s riskier to completely drain the tanks than to leave oil at what operators call the “working level” of a tank — in this case, about 1.7 million gallons, or a little more than half of what’s in each one now.
Preserving oil at the working level… makes it less likely it would float off its foundation in a severe flood, which would destroy its usefulness and risk a rupture that would leak residual hydrocarbons into the environment.
The potential environmental impact of six million gallons of crude vs residual hydrocarbons seems a no-brainer. Of course, the larger question is why the terminal is there in the first place.
From the Environmental News Service:
The Drift River terminal sits … in the middle of Cook Inlet’s rich and highly productive sport and commercial fisheries.
The Alaska Department of Fish and Game estimates the value of commercial and sportcaught fish in Upper Cook Inlet at well over $1.5 billion in 2008.
“We depend on clean and healthy Cook Inlet fisheries to feed our families,†said Tom Evans, an Alaskan Native from the Village of Nanwalek in Lower Cook Inlet. “It makes no sense to store oil at the base of an erupting volcano.â€
