400,000 gallons of radioactive water leaked from U.S. nuclear power plant in November 2022, disclosure delayed till now raising transparency and public safety concerns


19th March 2023 – (Washington) Minnesota regulators revealed that approximately 400,000 gallons of radioactive water had leaked from Xcel Energy’s Monticello nuclear power plant, located in the midwestern US state of Minnesota. The leak, consisting of 15 tons of liquid radioactive waste, occurred in November 2022 but was not made public until recently, causing concerns about transparency and public safety.

According to the Minnesota Pollution Control Agency (MPCA), state agencies are overseeing Xcel Energy’s efforts to clean up the “release of water contaminated with tritium” from the nuclear-generating plant. Xcel Energy reported the leak to the Minnesota Duty Officer and the U.S. Nuclear Regulatory Commission in November 2022, after noticing unusual results during routine groundwater monitoring.

Although the four-month delay in publicising the incident has raised concerns, the MPCA confirmed that the leak has been contained and has not contaminated the Mississippi River or drinking water sources. Additionally, there is no evidence indicating any potential risk to drinking water wells located near the plant.

Tritium, a naturally occurring radioactive form of hydrogen produced in the atmosphere, is a byproduct of electricity production in nuclear power plants. The leak occurred from a water pipe connecting two buildings at the Monticello facility, which Xcel Energy has since stopped.

The company has been monitoring the groundwater plume through two dozen wells while pumping contaminated groundwater through extraction wells. They are also exploring building aboveground storage tanks or installing a retention pond to store the tritium-containing water collected during ongoing recovery activities.

Kirk Koudelka, MPCA assistant commissioner for land and strategic initiatives, stated that they are working to ensure that the cleanup is thorough and poses minimal or no risk to drinking water supplies.

Although the incident has sparked concerns about transparency and public safety, industry experts have stated that the public was never in danger. Xcel Energy voluntarily notified state agencies and reported the leak of tritium to the Nuclear Regulatory Commission soon after confirming it. Victoria Mitlyng, a spokesperson with the Nuclear Regulatory Commission, emphasised that the public was not and is not in danger.

State officials confirmed that they knew about the leak in November but waited for more information before making a public announcement. “Now that we have all the information about where the leak occurred, how much was released into groundwater and that contaminated groundwater had moved beyond the original location, we are sharing this information,” said Michael Rafferty, a spokesperson for the Minnesota Pollution Control Agency.