Minnesota nuclear plant shuts down for repairs after second radioactive water leak.

Xcel Energy will shut down its Monticello nuclear plant in Minnesota earlier than planned due to another radioactive water leak. The company reported that hundreds of gallons of contaminated water, containing the radioactive isotope tritium, had leaked out since crews made temporary repairs. The plant will be powered down to make permanent repairs after 400,000 gallons of radioactive water leaked out beneath the facility late last year. The company insists the leak poses no risk to neighbors or the environment, and the shutdown isn't expected to impact electric service.