Xcel Energy removes 90% of tritium from groundwater below Monticello plant

Xcel Energy leak: City of Monticello learned of tritium in days, not weeks

The City of Monticello learned about elevated levels of tritium near the Xcel Energy nuclear plant three months earlier than city officials have acknowledged publicly, according to emails obtained from a public records request.

MONTICELLO, Minn. (FOX 9) - Xcel Energy said its teams have brought down the tritium concentrations in the groundwater beneath its Monticello nuclear plant by more than 90% since leaks were detected in late 2022. 

Monticello Nuclear plant leak 

Big picture view:

More than two years after a reported tritium leak that contaminated the groundwater beneath the Monticello Nuclear plant, Xcel Energy said it installed more than three dozen monitoring wells and retrieved millions of gallons of affected water.

Of those wells, only two, right below the plant structure, have tritium readings above the Environmental Protection Agency's (EPA) safe drinking water standard. 

READ MORE: Monticello nuclear plant shut down Wednesday after control valve issue

Xcel Energy officials said two other wells detected low levels of tritium near the Mississippi River, but both were below the EPA standard. In response, crews are adjusting the amount of water that is pumped to help control the flow of groundwater and recover more of it.

Officials add that "At no point has tritium been detected in the river itself above naturally occurring levels."

What's next:

Officials say they will continue to monitor and adjust their cleanup approach.

READ MORE: Radioactive leak at Monticello nuclear power plant; Xcel Energy cleaning it up

A regularly scheduled refueling outage is reportedly planned for Friday, April 18, which Xcel Energy said will not be impacted by the groundwater recovery work. However, residents and businesses in the area should expect increased activity at the plant and in the community as specialized contractors arrive to complete the work over the next month..

Dig deeper:

Another incident was reported earlier this year when the plant shut down because of a control valve issue. 

The initial tritium leak was reported in March 2023. However, it was later found that Xcel Energy officials were aware of the leak back in November 2022.

The plant was powered down after another leak was found about a week after the other was reported. 

READ MORE: Xcel to power down Monticello nuclear plant after new contaminated water leak