Xcel Energy Monticello Power Plant Tritium Leak

Currently, there is no health risk due to this situation. Monitoring wells are being sampled frequently to track the migration of the plume while the plant works to recover the tritiated water. Should the monitoring well results indicate protective action is necessary, it will be taken at that time.

The potential health risk from this event is the possibility of extremely small amounts of radiation exposure to the public. A conservative assumption in radiation protection is that any radiation exposure could result in an increase in cancer occurrences in the population, with the risk increasing as exposure increases. Tritium has not been detected, so there is no increase in cancer risk to the public. 

We have no evidence that there currently are impacts to public drinking water serving the plant or serving public water supplies in the vicinity of the plant.

• The closest public water supply well to the plume is more than a mile away in the opposite direction of groundwater flow. At this time, the plume has not migrated off the site. It would take years for the contamination to reach the closest wells. We do expect the mitigation activities to contain the plume. We will continue to monitor and assess the situation.
• We will work with Xcel on an appropriate plan to test drinking water at the plant to protect Xcel workers.

If the contamination would reach the river, we do not expect to find harmful amounts of tritium from the groundwater plume in downstream samples due to the volume of water moving through the river.

We have no evidence at this time to indicate impacts or risk to private wells in the vicinity of the plant. There are no private wells located in the direction of groundwater flow between the plume and the Mississippi River. We will continue to monitor water sources and evaluate the situation. MDH does not have plans to test private wells at this time. 

• Private Well Distances (PDF) - this map shows the approximate distance to known private drinking water wells in state databases within 1 mile of the release along with the direction that groundwater flows.
• Visit the Minnesota Well Index webpage to look up information on your private well. The Minnesota Well Index may not have information your well, especially if it was constructed prior to 1975. You can contact MDH at MNGP2023@state.mn.us if you are unable to find your well information.

If you would like to test your private well water for tritium

As a private well owner, you are responsible for regularly testing the water you use for cooking and drinking to make sure it is safe. Minnesota Department of Health (MDH) recommends that you test your well water for several contaminants. While MDH has not issued a recommendation for private well owners to test for tritium in response to the recent release at the Monticello plant, we want to make sure well owners have information about the issue and considerations.

• Learn more about general testing recommendations here: Well Testing, Results, and Options.
• We have no evidence at this time to indicate impacts or risk to private wells in the vicinity of the plant. The plume has not migrated off the site. If you would like information about well testing and tritium, please see Testing Your Private Well Water for Tritium (PDF).

Tritium does not bio-accumulate in people, animals or wildlife, crops or build-up in the environment. Tritium in the groundwater at the plant site will behave like water. It will not accumulate in food crops.

• Wildlife would not be affected.
• There is no risk to farmers who grow crops near the plant.