STANLEY- An estimated 840,000 gallons of emulsion spilled from a pipeline about 4 miles northwest of Stanley, Friday, Sept. 12, according to North Dakota Department of Environmental Quality (NDDEQ) information.

Emulsion is a mixture of crude oil and produced water flowing from the well head.

Hess Corp. notified NDDEQ of the spill Saturday, Sept. 13. The substance surfaced and flowed about 250 yards over agricultural land. No water resources have been impacted at this time.

The cause of the spill is under investigation.

Personnel from NDDEQ are inspecting the site and will continue to monitor the investigation and remediation efforts.