Federal investigators say a Canadian company's neglect of cracks in one of its oil pipelines and slow response to a 2010 rupture in southwestern Michigan caused the most expensive onshore spill in U.S. history.
National Transportation Safety Board investigator Matt Fox told board members in Washington on Tuesday that Enbridge, Inc., of Calgary, Alberta, knew about cracks in its pipeline near Marshall but failed to address them adequately before the rupture.
The July 2010 spill dumped 843,000 gallons of crude into the Kalamazoo River and an enjoining creek. Cleanup has cost an estimated $800 million and is only now nearing completion.
The five-member board will vote later Tuesday on whether to reject, amend or accept the investigators' findings.