WASHINGTON COUNTY (KSNT) – Federal officials say oil recovery operations in Washington County are complete following a massive oil spill late last year.

Kellen Ashford with the Environmental Protection Agency (EPA) said in a press release the restoration efforts for the area impacted by the Keystone pipeline oil spill on Dec. 8, 2022, is complete. Mill Creek, which bore the brunt of the oil spill, is flowing naturally now that the diversion system and berms have been removed. The final inspection of the area took place on Friday, Oct. 13, 2023.

Ashford said state officials with the Kansas Department of Health and Environment (KDHE) and U.S. Army Corps of Engineers (USACE) are continuing to monitor the area for the next five years or until it is determined these actions aren’t necessary anymore.

Workers on the oil spill were able to get to submerged oil impacts in Mil Creek following large-scale construction and engineering projects. Oil recovery efforts ceased in May 2023 at which point crews shifted to stream restoration work. More than 6,000 hours and 83 trips were taken by the EPA during this process.

Overall, more than 54 million gallons of contaminated water were treated and later released into Mill Creek. Ashford said more than 650,000 gallons of oil was recovered along with the remains of the pipeline after it ruptured. A total of 200,000 tons of oil-impacted soil, sediment and debris were excavated and sent to another location for disposal.

The Keystone oil spill impacted local animal life, leaving many animals dead or without a home. The spill drew criticism from a Kansas River conservation group as the scale of the spill became known.

The spill is recognized as the largest oil spill in the history of the Keystone pipeline. More than 580,000 gallons of oil were initially reported as having been dumped into Mill Creek, which feeds into the Kansas River, in a third-party investigation into the incident.

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