The United States Pipeline and Hazardous Materials Safety Administration, part of the Department of Transportation, has ordered the shutdown of TransCanada's Keystone Pipeline until it completes 14 steps respecting the safety and integrity of the line.
The line is currently shut down as a result of a leak and spill on May 27th in Kansas, and was shut down for an extended period earlier in the month as a result of a May 7 spill in North Dakota. The spills and the order come at a bad time for TransCanada, which is working hard to get United States approvals for its Keystone XL project.
The conditions required to restart include metallurgical testing, root cause failure analysis, a review of the rest of the system for similar concerns, the completion of permanent repairs, and ongoing monitoring.
UPDATE: The Pipeline and Hazardous Materials Safety Administration announced on June 4 that TransCanada had completed all of the steps required for the restart of the pipeline and could restart the line beginning on June 5. On June 6, TransCanada announced that it had begun transporting oil again.