US nuclear power plant leaks 400,000 gallons of radioactive water

Some 400,000 gallons of water containing tritium leaked at the Xcel Energy facility in Monticello, Minnesota. Photo / AP

A nuclear plant in the US leaked 400,000 gallons of radioactive water through a broken pipe, raising fears that the liquid has seeped into the ground.

Xcel Energy admitted that its Monticello facility, approximately 60 kilometres northwest of Minneapolis in the state of Minnesota, suffered a leak of water containing tritium last November.

However, the company did not explain why it waited more than three months to publicly acknowledge what happened.

Xcel Energy said that it notified state officials and the federal Nuclear Regulatory Commission once it learned of the leak on November 22, 2022, but it was not announced until this week.

Chris Clark, the company’s president, said in a statement: “While this leak does not pose a risk to the public or the environment, we take this very seriously and are working to safely address the situation.”

Toxic water ‘did not reach Mississippi River’

The Minnesota Pollution Control Agency said that Xcel Energy told it some 400,000 gallons of water containing tritium leaked at the site, but none “reached the Mississippi River or contaminated drinking water sources”.

State officials “are actively reviewing data” from the site and “overseeing remediation efforts”, the agency said.

Xcel Energy said it has “recovered about 25 per cent of the tritium released and will continue recovery over the course of the year”.

The leak originated in “a water pipe between two buildings” at the Monticello plant.

Tritium is a radioactive isotope of hydrogen that is a byproduct of the production of electricity at nuclear plants. It can also occur naturally in the environment.

Spill detected ‘during groundwater testing’

Xcel Energy said that it detected the spill while doing routine groundwater testing.

It added that it contained the leak by diverting water to an in-plant treatment facility and will need to build “large storage tanks to store recovered water until it can be treated and re-used”.

The company said it is conducting more frequent tests from some two dozen groundwater monitoring wells in and around the site.

The US has suffered one major nuclear accident in its history: the meltdown of the Three Mile Island reactor in Pennsylvania on March 28, 1979.

Some 92 nuclear reactors provide power to tens of millions of American homes. Smaller accidents have occurred over the years, but were usually contained with only localised impacts.