Monticello nuclear plant leaked 400,000 gallons

Xcel Energy announced Thursday its Monticello Nuclear Generating Plant leaked water that contained radioactive tritium last year.

Details: Xcel said it confirmed the leak to federal regulators and the Minnesota Pollution Control Agency on Nov. 22. Xcel patched it soon after it found the source on Dec. 19, according to the Star Tribune.

What they're saying: Xcel said tritium emits low levels of radiation that are similar to what is found in food people eat. It said the spill "poses no health and safety risk to the local community or the environment."

• The Star Tribune said that 400,000 gallons leaked into the groundwater.

Threat level: Xcel said it's recovered 25% of the tritium and will continue to do so over the next year. Once recovered, the water is treated and reused.

• It said it's monitoring two dozen wells on the site, and the spill is "fully contained on-site and has not been detected beyond the facility or in any local drinking water."

Yes, but: This is the first public announcement of a leak that regulators knew about four months ago.

• The Star Tribune asked MPCA assistant commissioner Kirk Koudelka why the public wasn't notified earlier, and he said, "We have now sufficient information to be able to share it out to a wider group."