Mar 18, 2023 - Energy & Environment

Everything we know about the Minnesota nuclear plant leak

Monticello nuclear power plant.

Monticello nuclear power plant. Photo: Education Images/Universal Images Group via Getty Images

Minnesota agencies said this week that they are monitoring the cleanup of a 400,000-gallon radioactive water leak from a nuclear power plant outside Minneapolis from last November.

Driving the news: The leak was contained to the plant site in Monticello and it poses no health or safety risks to the community or nearby environment, according to Xcel Energy, a Minneapolis-based utility company.

  • The plant leak was not revealed to the public until now because it "poses no health and safety risk to the local community or the environment," the company said in a statement.
  • The plant in Monticello is about 35 miles northwest of Minneapolis and upstream from the Mississippi River, per AP.

Minnesota nuclear plant leak details

The leak, which occurred at the Monticello Nuclear Generating Plant, was first reported to the Nuclear Regulatory Commission (NRC) and the state of Minnesota on Nov. 22, 2022, Xcel said.

  • The leak never reached the threshold that would have required a public announcement, the company said.
  • Xcel said it has since worked with state and federal regulators, as well as local officials, to monitor the cleanup. The company added that it "has been pumping, storing, and processing the water for reuse."

What they're saying: "We have taken comprehensive measures to address this situation on-site at the plant," Chris Clark, president of Xcel Energy–Minnesota, North Dakota and South Dakota, said in a statement.

  • "While this leak does not pose a risk to the public or the environment, we take this very seriously and are working to safely address the situation," he added.
  • Victoria Mitlyng, a spokesperson with the Nuclear Regulatory Commission, told KARE 11 that "the public in Minnesota, the people, the community near the plant, was not and is not in danger.”

What we know about the leaked water

The Minnesota Pollution Control Agency said in a statement Thursday that the leak was "stopped and has not reached the Mississippi River or contaminated drinking water sources."

  • "There is no evidence at this time to indicate a risk to any drinking water wells in the vicinity of the plant," the MPCA said.

The leaked water contained levels of tritium, a compound that "is naturally present in the environment and is commonly created in the operation of nuclear power plants," Xcel said.

  • Tritium can release low levels of radiation, but on a similar level as common materials and food, the company said.
  • The compound can be created from electricity production at nuclear power plants, according to the Minnesota PCA.
  • Xcel said it has recovered about 25% of the tritium released and will continue to do so over the next year.
  • Edwin Lyman, director of nuclear power safety with the Union of Concerned Scientists, told KARE 11 that there would only be a health risk if people consumed a high amount of tritium.

What's next: Clark, of Xcel Energy, said the company will "continue to gather and treat all potentially affected water while regularly monitoring nearby groundwater sources."

  • The MPCA said that Xcel is exploring the possibility of building aboveground storage tanks or a retention pond to store the contaminated water that has been recovered.


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