Montana Governor Brian Schweitzer commented on the Yellowstone River pipeline spill yesterday saying, “I can tell you right now, I am gonna stay on this like smell on a skunk until it’s cleaned up.” Well, there does seem to be a smell and it’s not benzene and it’s not oil and it seems to be mostly emanating from the boardrooms of ExxonMobil Corporation.
In what seems to have become SOP for the oil giant, they told federal regulators today that their pipeline was buried 12 feet below the streambed of the Yellowstone. On Tuesday ExxonMobil Pipeline Co. President Gary Pruessing said, before talking to the Exxon PR department, “Soundings to determine the pipeline’s depth were taken in December, and at the time, the line appeared to be 5 to 8 feet below the riverbed,”. On Tuesday, a company executive told the Governor that they had shut the line down within 30 minutes of the spill. The new documents show that the pipe leaked for nearly an hour before being shut down. Initially, company spokesmen said that they saw “very little soiling” of the river banks beyond the 10-mile mark. Currently the company has workers sopping up oil along a 25-mile stretch of the river and there were reports of a 25-mile long slick near Hysham, nearly 100 miles downstream. In 1990, Exxon admitted that they had spilled 500,000 gallons of heating oil after the Coast Guard questioned their original estimate of 5,000 gallons.
I’m willing to give Exxon the benefit of the doubt if they fulfill their obligation and restore the damage they have done, but I’m not real comforted by their efforts so far. There is not much chance that they will get more than a small fraction of the oil they dumped in the river. You can’t wipe sticky black goo off a hawthorne bush and seeing a couple of hundred guys out there with paper towels in the grass isn’t very reassuring. I’m also not reassured when they keep changing their story to fit new facts. At a depth of 5-8 feet, there wasn’t much chance of the pipeline not being exposed during a 100-year flood event, but when DOT told them that they needed to bury the pipe more deeply, they arbitrarily changed that claim to 12 feet.
C’mon guys, rivers scour! There are many, many models that will estimate the depth you need to bury something below a river to escape the scour. Unless Exxon doesn’t have any engineers on staff, they can figure that out. Quit guessing. In the Missouri River they are documenting scour of 40-50 feet from current flows. Sure, the Yellowstone ain’t the Missouri, but 60,000 cfs is still a lot of water. If you know stuff like the depth of flow, slope of the river bed, velocity of flow, type of bed material, etc. you can predict how deep to bury a pipe. It’s not guesswork. Pipeline companies don’t design around stopping a failure, they design around how often failure will occur based on how much they want to spend and that doesn’t give me a lot of confidence that this won’t happen again.