The US Nuclear Regulatory Commission has renewed for a second time the operating licence of the boiling water reactor (BWR) at unit 1 of the Monticello Nuclear Generating Plant in Minnesota for an additional 20 years. Its operating licence will now expire on 8 September 2050.
The NRC’s review of the application from Northern States Power Company-Minnesota (doing business as Xcel Energy), proceeded on two tracks. A safety evaluation report was issued in March 2024, and a final environmental impact statement was issued in November 2024.
With the renewal of the Monticello license, nine US commercial nuclear power reactors have received subsequent renewed licences (authorising operations from 60 to 80 years). Six applications for subsequent licence renewal are currently under review.
Xcel Energy said it will now seek a matching licence extension from the Minnesota Public Utilities Commission. State regulators had previously approved the Monticello plant to operate until 2040.
The plant, which opened in 1974, recently came under scrutiny when a faulty pipe leaked water contaminated with tritium, a radioactive form of hydrogen, into the soil and groundwater near the Mississippi River. Xcel officials said no contamination was detected in the river. The leak was first detected in November 2022, but the public was not notified until March 2023. Federal officials designated the event as a “non-emergency,” and during a 2023 meeting discussing Xcel’s application for a 20-year renewal, NRC assured the community that the spill “does not affect public health and safety”.
