A leak of 400,000 gallons of radioactive water from Xcel Energy, a  nuclear power plant in Monticello, Minnesota, was reported Thursday, and the state's regulators said they are watching the cleanup.

According to Valley News, state officials said the Monticello nuclear-generating plant leaked water in late November that contained radioactive tritium.

However, the spill was only made public on Thursday as state officials said they waited for more information.

Minnesota Pollution Control Agency spokesman Michael Rafferty said: "We knew there was a presence of tritium in one monitoring well. However, Xcel had not yet identified the source of the leak and its location."

Rafferty noted that they are now sharing this information after they got all the information they need, like "where the leak occurred, how much was released into groundwater," and whether contaminated groundwater had moved beyond the original location.

According to Rafferty, the water remains contained on the company's property and poses no immediate public health risk.

Xcel Energy also assured that there is no danger to the public. In a statement, the company said it "took swift action to contain the leak to the plant site, which poses no health and safety risk to the local community or the environment." 

The leak was determined to have originated in a pipe connecting two buildings. The company noted that it contacted the state and the federal Nuclear Regulatory Commission (NRC) the next day, on November 22.

Since then, it has been extracting water from the ground and storing and treating the contaminated water that contains tritium, which levels are below federal thresholds.

Based on the ongoing monitoring from more than two dozen on-site monitoring wells, Xcel Energy said the leaked water had not been found outside the facility or in any nearby drinking water.

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What Is Tritium?

According to CBS News, tritium is a naturally occurring radioactive hydrogen isotope and a byproduct of nuclear power plants.

The NRC said it generates a mild kind of beta radiation that does not move very far and does not penetrate human skin. A person would only get a little dose if they accidentally drank water from the spill.

The NRC noted that while tritium spills occasionally occur at nuclear power plants, it has repeatedly determined that they have either been contained on the plant property or involved such low offsite levels that they had no adverse effects on public health.

Radioactive Water Leak Incident Already Happened at the Same Minnesota Nuclear Plant

According to NRC, a similar tritium leak already occurred at the Minnesota nuclear plant in 2009.

The commission estimated that at least 40 of the 57 nuclear power reactors in the United States had experienced tritium leakage at some point, KARE 11 reported.

However, the NRC noted that none of these cases released contaminated water into outside groundwater or drinking water.

In a statement released on Friday, Monticello Mayor Lloyd Hilgart said the city discovered the leak's entire nature in late February.

"Though the Xcel plant is within our community, the City of Monticello has no authority to govern the nuclear plant. As we've noted, the federal and state regulating agencies determine the appropriate governmental responses to incidents at the Xcel nuclear plant, including any emergency response, remedial actions, and public or media releases," the mayor noted.

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This article is owned by Latin Post.

Written by: Bert Hoover

WATCH: Xcel Energy Cleaning up Radioactive Leak in Monticello - From WCCO - CBS Minnesota