WASHINGTON, June 4 (Reuters) - The Keystone XL oil pipeline project would be vulnerable to attacks that could cause heavy crude to be spilled in farm regions dependent on fresh water, according to a report by NextGen Climate, a political group led by billionaire activist Tom Steyer.
Attackers could damage remote pump stations along the pipeline's route in the northern Great Plains with just 4 pounds (1.8 kg) of readily available 1960s-era explosives, Dave Cooper, a former Navy Seal, said in the 14-page NextGen report released Wednesday.
Under Cooper's most likely scenario, coordinated bomb attacks could cause a spill of 68,095 barrels of oil that would be difficult to clean up from rivers and aquifers.
"A coordinated attack at several critical points would not only wreak havoc ... it would likely overwhelm the existing engineering capability needed to clean it up," Cooper said in the report, some of which was redacted for public readership.
The report was the latest move by Steyer, a San Francisco-based hedge fund investor and climate change activist, to fight TransCanada Corp's Keystone XL pipeline, which critics say would increase emissions linked to climate change.
Supporters of Keystone, which would link Canada's vast oil sands with refineries in Texas, say it would bolster North American energy security and provide thousands of jobs.
Earlier this year, Steyer pledged to spend $100 million to back pro-environment candidates in congressional campaigns ahead of the Nov. 4 U.S. elections.
Cooper, who looked at details of the pipeline available on the Internet and walked the length of another TransCanada oil pipeline called Keystone 1, said he was able to freely approach a pump station on the line for 15 minutes while snapping photos.
"I was not approached, questioned or even noticed at any point," he said in the report.
The State Department has delayed a decision on Keystone XL, pending a legal matter in Nebraska that may not be resolved for several months. (Reporting by Timothy Gardner; Editing by Ros Krasny and Bernadette Baum)