(MONTICELLO, Minn.) — A Minnesota nuclear power plant that spilled 400,000 gallons of radioactive water last year is being temporarily shut down after a minor leak was discovered this week.
Xcel Energy said it will begin shutting down its Monticello facility on Friday to expedite repairs needed to permanently fix a leak of tritium-contaminated water. The duration of the shutdown has not yet been determined, but it shouldn’t affect power to customers, the Minneapolis-based utility said.
Xcel Energy and state agencies publicly announced last week the initial leak of about 400,000 gallons of water containing tritium — a byproduct of electricity generation at nuclear power plants that emits low levels of radiation.
The first leak was detected by routine groundwater monitoring systems in late November and occurred in a water line that runs between two buildings at the facility, which is located along the Mississippi River about 40 miles northwest of Minneapolis.
The leak poses no health and safety risk to the local community or the environment, and tritium levels are below the Nuclear Regulatory Commission’s safety thresholds, Xcel Energy said. State officials who oversaw the cleaning of the water also said the leak did not reach the Mississippi River or contaminated drinking water sources.
Xcel Energy said it caught the water from the leaking pipe and piped it back to the facility for reuse until it could install a replacement pipe in mid-April. However, on Wednesday, monitors indicated that over the past two days, “a small amount of new water from the original leak had reached the groundwater,” the company said in a news release on Thursday.
The new leak is estimated at “hundreds of gallons” and “will not materially increase the amount of tritium that the Company is working to recover and poses no risk to health or the environment,” Xcel Energy said.
Continued monitoring has revealed that the spilled water “remains totally contained on site and was not detected outside the facility or in any local drinking water,” the company said.
“While the leak continues to pose no risk to the public or the environment, we have determined that the best course of action is to shut down the facility and make the permanent repairs immediately,” Chris Clark, President of Xcel Energy – Minnesota, North Dakota and South Dakota said in a statement. “We continue to work with and update our state, federal, city and county leaders in this process.”
The company told state officials Thursday that the new leak is ongoing, according to the Minnesota Pollution Control Agency, which works with the Minnesota Department of Health and Human Services to oversee cleanup of affected groundwater.
The agencies said they were “encouraged” by the “immediate action” Xcel Energy took to fix the leak.
“State authorities currently have no indication of any current or imminent risk to the public and will continue to monitor groundwater samples. Should an immediate risk arise, we will notify the public immediately,” the Minnesota Pollution Control Agency said in a statement Thursday.
So far, about 32% of the released tritium has been recovered, Xcel Energy announced on Thursday.
Copyright © 2023, ABC Audio. All rights reserved.
