Monticello nuclear plant powers down to fix radioactive water leak

Minneapolis-based Xcel Energy is to begin powering down its Monticello nuclear plant to permanently fix a tritium leak.

In November 2022, the company found that approximately 400,000 gallons of water containing tritium had leaked out.

Xcel Energy implemented a short-term solution to capture water from the leaking pipe and reroute it back into the plant for re-use.

The solution was aimed at preventing any new tritium from reaching the groundwater until a replacement pipe could be installed during a scheduled refueling outage in mid-April.

However, monitoring equipment at the plant has found new water from the original leak has reached the groundwater.

Have you read?
Why ‘nuclear energy is the answer to the climate emergency’
GE’s boiling water reactor selected for Estonian SMR plant

Upon investigation, operators discovered that 100% of the leaking water is no longer being captured. The new leakage however, according to Xcel Energy, "will not materially increase the amount of tritium the company is working to recover and does not pose any risk to health or the environment".

Chris Clark, president of Xcel Energy–Minnesota, North Dakota and South Dakota, said: “While the leak continues to pose no risk to the public or the environment, we determined the best course of action is to power down the plant and perform the permanent repairs immediately.”

The statement from Xcel Energy confirms that "the leaked water remains fully contained on-site and has not been detected beyond the facility or in any local drinking water".

So far, Xcel Energy has recovered about 32% of the tritium released and will continue recovery over the course of the next year.

The schedule for resuming operation at the nuclear plant is still to be determined, with scheduled refueling to take place in Spring this year.

Tritium is a compound that is naturally present in the environment and is commonly created in the operation of nuclear power plants. It emits low levels of radiation and is not harmful in small amounts.