The central issue involving the Keystone XL pipeline across Nebraska is what Trans-Canada would do to prevent leaks and stop those that do occur.
The bar on this issue has been raised by two developments: the Yellowstone River pipeline break, and a new report from a University of Nebraska-Lincoln professor.
A year ago, a World-Herald editorial said that Nebraskans need information on all key aspects of the proposed Keystone XL pipeline before it's built across the Ogallala Aquifer, perhaps the most precious water resource in the state.
Earlier this month, an Exxon pipeline running under the Yellowstone River in Montana ruptured, spilling 42,000 gallons of crude oil and threatening a significant section of the river and, potentially, the Missouri River system to the Mississippi. TransCanada, the company planning the pipeline, said it would bury the 36-inch pipe 25 feet deep to prevent breakage where it passes under major watercourses.
At smaller streams, there is a concern about scouring — water eating away at the soil above a pipeline. That's what caused the Montana spill.
At the crossings of smaller streams, the depth for the Keystone XL pipeline generally would be 5 feet. That's the depth of the broken Exxon pipeline. A TransCanada official told The World-Herald that in areas where scouring is a concern, the depth would be adjusted lower and crossing sites would be changed.
In light of the Yellowstone River leak, then, Nebraskans will rightly expect, and need to receive, complete information and full assurance about pipeline depth at smaller streams.
* * *
The second recent development involves UNL engineering professor John Stansbury, who has worked extensively with water resources and hazardous waste management. He was an instructor for the U.S. Army Corps of Engineers' risk assessment program.
Stansbury has issued a report expressing concern about the pipeline plans in various ways. He said his motive for the study was to provide independent, unbiased information. He enlisted help from the environmental group Friends of the Earth, which has been critical of the project, to distribute the report.
His study concludes that a major spill from the Keystone pipeline could contaminate drinking water used by people in Omaha, Lincoln and downstream to Kansas City, Mo. He calculated that the pipeline would break almost eight times more than TransCanada estimated.
The UNL professor wrote that "TransCanada Corp. made significantly flawed and inappropriate assumptions about the frequency and severity of expected spills."
Stansbury calculated a worst-case scenario for a Sand Hills pipeline break, suggesting that more than 7.9 million gallons of oil could be released. That could result in an oil plume 40 feet thick by 500 feet wide by 15 miles long in the Ogallala Aquifer.
A break where the pipeline crosses the Platte River could affect even more Nebraskans, the professor suggested.
He wrote that the company's assumptions about the response time were "wildly optimistic."
Sen. Mike Johanns said Stansbury's report showed "yet again" that it's right to raise questions about the pipeline route.
Last month, the federal Environmental Protection Agency expressed concern that TransCanada's reliance on pressure drops and aerial surveys to detect leaks would be inadequate for detecting smaller spills.
* * *
TransCanada makes a range of points on these issues. The company's CEO mentions several in an essay on the More Commentary page today. The company says Stansbury's report places one questionable assumption upon another.
Leaks would be smaller in quantity than Stansbury estimated because they would be detected and shut off faster, according to the company.
TransCanada says that at river crossings, it will bury the pipeline deeper and use heavy-walled pipes. TransCanada says its methods to protect against external corrosion have "virtually eliminated failure" in their 25-plus years of use.
Leaks along the existing Keystone line, company officials say, all have occurred at valves and pumping stations and were contained within the pump station areas. TransCanada says it has accurately used industry standards in calculating risk probabilities; it says Stansbury relied on incorrect assumptions about the oil's corrosive potential.
Most Nebraskans aren't experts on pipeline technology, and many Nebraskans disagree about this pipeline. But everyone can agree that at a minimum, this proposed project should not go forward unless Nebraskans receive the needed information about every aspect of pipeline safety, in order to reach informed, responsible judgments.
And our congressional delegation should insist that any State Department analysis and recommendations address these concerns completely.
On this issue, the bar is quite high, and it just got higher.
Copyright ©2012 Omaha World-Herald®. All rights reserved. This material may not be published, broadcast, rewritten, displayed or redistributed for any purpose without permission from the Omaha World-Herald.
