400,000 gallons of radioactive water leak from Minnesota power plant

News

from Patrick Riley

March 18, 2023 | 1:39 in the morning

At least 400,000 gallons of radioactive water leaked from a Minnesota nuclear power plant in November, but officials did not publicly disclose the spill until Thursday.

Minnesota regulators shared the disturbing development Thursday and said they are monitoring the cleanup from Xcel Energy’s Monticello nuclear plant.

While the power company reported the tritium-laced water leak to state and federal authorities and the Nuclear Regulatory Commission last fall, state officials said they waited to tell the public until they had more information.

The four-month delay in announcing the leak to the public raised concerns about public safety and transparency. However, industry experts said Friday that there was never a threat to public health because the radioactive water never reached a threshold that would have required public notification.

“It’s something we struggle with because there’s such concern about anything nuclear,” said Victoria Mittling, a spokeswoman for the Nuclear Regulatory Commission. “The concern is very, very understandable. That’s why I want to make clear the fact that the public in Minnesota, the people, the community near the plant were not and are not in danger.

Minnesota Pollution Control Agency spokesman Michael Rafferty said Thursday that officials knew one of the plant’s monitoring wells contained tritium in November, but “Xcel has not yet identified the source of the leak and its location.”

“Now that we have all the information about where the leak occurred, how much was released into the groundwater and that the contaminated groundwater has moved away from the original location, we are sharing that information,” Rafferty said.

Xcel said the leak came from a pipe between two buildings.

Tritium is a radioactive isotope of hydrogen that occurs naturally in the environment and is a common byproduct of nuclear power plant operations. It emits a weak form of beta radiation that does not travel very far and cannot penetrate human skin, according to the Nuclear Regulatory Commission.

The chemical poses a health risk only to people who have consumed large amounts of tritium, according to Edwin Lyman, director of nuclear safety at the Union of Concerned Scientists. The risk is contained if the plume remains on the company’s site, Xcel Energy and Minnesota officials said.

Lyman said if officials are sure it hasn’t left the power plant’s confines, people shouldn’t worry about their health or safety.

“Xcel Energy took swift action to contain the spill to the plant site, which did not pose a risk to the health and safety of the local community or the environment,” the Minneapolis-based company said in a statement.

Mittling said nuclear plants are not required to report all tritium leaks to the Nuclear Regulatory Commission, but Xcel agreed to report certain leaks to the state, which in turn shares it with the commission.

On Nov. 23, the commission posted a notice about the leak on its website, which it classified as non-urgent and said it was under investigation. No other notice had been provided to the public as of Thursday.

There’s no way tritium can get into drinking water, Mittling said. The power plant has groundwater monitoring wells, and plant officials regularly track the progress of contaminants by looking at which wells detect higher amounts.

Xcel said it has recovered about 25 percent of the spilled tritium so far, as Nuclear Regulatory Commission inspectors are also on site monitoring the response.

The company said it plans to install a permanent solution this spring.

With postal cables