• 400,000 gallons of water laced with tritium leaked from Xcel Energy's power plant in Monticello
  • The leak came from a pipe between two buildings at the site
  • Xcel Energy has reportedly recovered about 25% of the tritium released

Authorities are monitoring the cleanup of a leak at a nuclear power plant in Monticello, Minnesota, after 400,000 gallons of water laced with the radioactive isotope tritium spilled from a pipe at Xcel Energy's plant.

The leakage, which happened in November, is contained to the site and there is no danger to the public, officials said, Bloomberg reported.

Although the state and federal authorities were informed immediately after the spill was confirmed on Nov. 22, it was made public only on Thursday as the officials were awaiting more information.

"With no immediate safety risk, we focused on investigating the situation and containing the affected water in concert with our regulatory agencies," Xcel Energy spokesperson Kevin Coss told the outlet.

Xcel had spotted the presence of tritium in a monitoring well but had not identified the source at the time of the spill, Minnesota Pollution Control Agency (MPCA) spokesman Michael Rafferty said, reported ABC News Go.

Tritium is a radioactive isotope of hydrogen that causes a weak form of beta radiation and is a common byproduct of electricity production in nuclear power plants.

The company eventually identified the leak came from a pipe between two buildings at the power plant and it had been pumping contaminated water through extraction wells. The tritium levels in the contaminated water are below federal thresholds, officials said.

"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," Rafferty said, adding the leak has not left the facility.

Xcel Energy confirmed the leaked water was fully contained on-site. It has reportedly recovered about 25% of the tritium released.

"Ongoing monitoring from over two dozen on-site monitoring wells confirms that the leaked water is fully contained on-site and has not been detected beyond the facility or in any local drinking water," Xcel Energy said in a statement.

The company is looking to build above-ground tanks to store contaminated water. State regulators will review their options for treatment and disposal.

MPCA said it will closely monitore the cleanup activities at the site.

"Our top priority is protecting residents and the environment, and the MPCA is working closely with other state agencies to oversee Xcel Energy's monitoring data and cleanup activities. We are working to ensure this cleanup is concluded as thoroughly as possible with minimal or no risk to drinking water supplies," said Kirk Koudelka, MPCA assistant commissioner for land and strategic initiatives.

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