Xcel Water Leak at Monticello Plant

Tritium (H-3) is a weakly radioactive isotope of the element hydrogen that occurs both naturally and during the operation of nuclear power plants. Tritium has a half-life of 12.3 years and emits a weak beta particle. The most common form of tritium is in water, since tritium and normal hydrogen react with oxygen in the same way to form water. Tritium replaces one of the stable hydrogens in the water molecule, H2O, and creates tritiated water, which is colorless and odorless.

Tritium can be found in self-luminescent devices, such as exit signs in buildings, aircraft dials, gauges, luminous paints, and wristwatches. It is also used in life science research and in studies investigating the safety of potential new drugs. Click here for more information from the EPA.

The public water system operated by the City of Monticello has been unaffected by the leak at the Monticello Xcel Energy Facility. 

The source for the City of Monticello municipal water system is from five deep wells located east of State Highway 25. As part of the City’s wellhead protection plan, the areas of influence for the city’s wells and the flow path for the corresponding aquifer have been modeled.  

The area where the leak occurred is outside of this wellhead protection area and outside of the area where modeling showed our wells draw. Xcel Energy has their own monitoring wells that are separate from the City of Monticello’s water system. The Xcel system is where the contamination was detected.

We’re committed to providing information and answering any questions as more information continues to become available.

The Nuclear Regulatory Commission and Minnesota Department of Health continue to monitor the contaminated groundwater at the Xcel Energy Nuclear Generating Plant. While city officials are confident in the agencies and the science showing the tritiated water has not left the Xcel Energy site, we want to ensure the public feels the same confidence. We are working with a private vendor to test samples from the 5 municipal wells for tritium. When those results are available, we will notify the public via our regular communication channels: Utility Bill insert, City website/News Flash, e-news, and social media channels.

We understand the notification from Xcel Energy and the State of Minnesota may cause public concern. We encourage members of the public to use the resources and contact button on Xcel Energy's website for questions about the leak and the plant. While our local leaders continue to monitor the situation, the response and containment of the leak are being managed by agencies of the State of Minnesota and Xcel Energy. 

The public water system operated by the City of Monticello has been unaffected by the leak at Xcel. We’re committed to providing information and answering any questions as more information continues to become available.

If there is any impact to our drinking water supply or infrastructure, we will immediately notify the public with assistance from coordinating state agencies. For immediate text and email alerts in the event of future public safety messages, residents can subscribe to our City Alerts Program.

Additional Contact Information

• For residents that have concerns about private wells, contact Jennifer Weier at MN Department of Health (Jennifer.weier@state.mn.us or 651-201-3658) 
• For residents with general questions, contact Steve Mikkelson at MPCA (stephen.mikkelson@state.mn.us or 218-316-3887)

Xcel Energy identified the source of the leak as a water pipe running between two buildings. To contain the leak, the facility is diverting the water to an in-plant water treatment system, preventing additional water from leaving the plant, and will install a permanent solution in the spring of 2023. A thorough inspection was conducted of all piping in all locations where a leak could occur, to verify that no other area of the facility was facing this issue. The company will also be examining the one pipe that did leak in a laboratory to better understand why this happened. These findings will help Xcel Energy ensure it does not encounter the same issue moving forward.

Xcel Energy notified the Nuclear Regulatory Commission (NRC) as well as the state when the leak was confirmed. The company has since coordinated regularly with regulators as the company has been pumping, storing, treating and reusing the leaked water.

Xcel Energy has indicated that ongoing monitoring from over two dozen on-site monitoring wells confirms that the leaked water is fully contained on-site and has not been detected beyond the facility or in any local drinking water. State agencies continue to monitor Xcel Energy’s remediation work to ensure the continued safety of the local community and surrounding environment.

The company has constructed new monitoring and recovery wells and has increased the frequency of measurements from its network of over two-dozen groundwater monitoring wells to enhance its monitoring and recovery efforts. Large storage tanks are also likely to be constructed on-site to store recovered water until it can be treated and reused.

The federal and state regulating agencies determine the appropriate governmental responses to incidents at the Xcel nuclear plant, including any emergency response, remedial actions and public information and media releases. If there is any impact to our drinking water supply or infrastructure, we will immediately notify the public with assistance from these agencies. For now, we will continue to advocate for our community and participate in the response as appropriate at the city-level.

For more information click on the following links:

• Xcel Energy: Press Release, March 16, 2023
• Minnesota Pollution Control Agency: Press Release, March 16, 2023
• Xcel Energy: Monticello Groundwater
• U.S. Dept of Health: Xcel Energy Tritium Leak Resources
• U.S. Nuclear Regulatory Commission: Groundwater Contamination (Tritium) at Nuclear Plants
• U.S. Nuclear Regulatory Commission: Backgrounder on Tritium, Radiation Protection Limits, and Drinking Water Standards