The Arkansas spill shone a spotlight on the dangers hiding in existing pipelines. It also reignited the debate over the proposed Keystone XL.

By Lisa Song

When a 65-year-old ExxonMobil pipeline ruptured on March 29 and spilled 210,000 gallons of oil in Mayflower, Ark., it opened the nation's eyes to the potential dangers lurking in the thousands of miles of aging and overlooked pipelines buried beneath neighborhoods and farms.

The spill also brought fresh attention to the debate over the proposed Keystone XL pipeline and the inherent risks of transporting Canadian tar sands across America's heartland. Exxon's Pegasus pipeline was carrying dilbit when it split open on Good Friday, the same type of tar sands oil that would run through the Keystone. A separate, much larger dilbit spill in Michigan is still being cleaned up more than three years later.


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