North Dakota regulators are proposing a fine of at least $15,000 against the company building the four-state Dakota Access pipeline.
The Public Service Commission said Monday in a complaint that a subsidiary of Texas-based Energy Transfer Partners didn't get regulators' approval to proceed with construction after artifacts, including stone cairns, were found last month.
• FAQ: The Dakota Access pipeline and protest
The company diverted construction so the artifacts weren't disturbed, a plan the State Historic Preservation Office concurred with. But the PSC says the company should have gotten clearance from regulators.
Energy Transfer Partners can agree to a fine or request a hearing. Spokeswoman Vicki Granado says the company doesn't think it did anything wrong but is working with the PSC.
The $3.8 billion pipeline will carry North Dakota oil through South Dakota and Iowa to Illinois.