MONTICELLO (WJON News) -- A mechanical failure at the Monticello Nuclear Power Plant led to an oil leak on Tuesday morning.

Xcel Energy officials say none of the oil entered the Mississippi River. Xcel says they immediately notified federal, state, and local officials of the incident.

The nuclear plant has been shut down since February 20th for maintenance. Xcel says operators were testing some equipment when they noticed low oil levels in one of the motors that circulates water through the plant for cooling.

The workers discovered that a part that separates the lubricating oil and the water had failed, causing the two to mix. Officials say a portion of the oil made it to the discharge canal before operators isolated the equipment and sealed it off with absorption booms and containment equipment.

Xcel says about 200 gallons of oil left the cooling equipment before they shut it down.

Plant operators continue to monitor the situation as they clean up the site.

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