Operations have resumed on the Keystone Pipeline System after a rupture resulted in 3,500 barrels of oil spilled in southeastern North Dakota. South Bow, the company that owns the pipeline, confirmed Wednesday that it had received approval from the Pipeline and Hazardous Materials Safety Administration (PHMSA) to restart the pipeline with reduced operating pressures. 

As of Monday, according to the company’s statements, most of the oil that was spilled has been recovering, and South Bow is working to remediate the impacted soil.

The company will continue to monitor the system as operations resume and investigate the cause of the rupture, which is still unknown. 

The Keystone Pipeline System transports energy across 2,689 miles, from Canada to refining markets in Illinois, Oklahoma and Texas. According to the Liquid Energy Pipeline Association, total liquid pipeline incidents are down 23% over the past five years, even though pipeline mileage and barrels delivered have increased by approximately 5%.