CALGARY — TC Energy Corp. says it has restarted the southern extension of its Keystone pipeline after repairing a Dec. 7 leak that led to the worst oil spill in the pipeline's history.

The Calgary-based company says it will operate the pipeline under plans approved by U.S. regulators, including additional safety measures such as reduced operating pressure.

TC Energy restarted most of the 4,324-kilometre Keystone pipeline system on Dec. 14, while the 154-km Cushing Extension, running from just south of Steele City, Nebraska to Cushing, Oklahoma, had remained shut following the leak.

The cause of the estimated 14,000-barrel spill, which eclipsed a 2017 6,600-barrel spill in North Dakota and a 2019 4,500-barrel spill in South Dakota, is still under investigation.

The company says it is committed to remediate the spill site in Washington County, Kansas, which includes a stream and agricultural land.

A report released last year from the U.S. Government Accountability Office (GOA), a congressional watchdog agency, said Keystone's accident history has been similar to other crude oil pipelines since 2010, but the severity of spills has worsened in recent years.

This report by The Canadian Press was first published Dec. 29, 2022.

Companies in this story: (TSX:TRP)

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