In March the City of Monticello submitted water samples from our municipal wells to a private vendor to test for tritium. The results confirm the city drinking water supply is safe and well below the EPA's drinking water standards for tritium levels.
City officials continue to be confident in the scientific analysis by federal and state agencies that show the tritiated water plume has not left the Xcel Energy site and has not impacted the safety of Monticello’s public water system. However, city leaders want to ensure the public feels the same confidence in their drinking water.
The tritium-related health limit established by the Environmental Protection Agency for drinking water is 20,000 pCi/L (picocuries per liter). The highest sample result from Monticello’s municipal wells was 209 pCi/L, the lowest was 33.9 pCi/L. All results were well below the EPA's tritium-related health limit. These results support state agency assertions that the plume has not migrated off-site or impacted municipal drinking water.
Tritium is a naturally occurring form of hydrogen that is produced in the upper atmosphere. According to the EPA, "Levels of naturally occurring tritium in the atmosphere produced by cosmic rays are constant." As a result, low levels of tritium are commonly found in drinking water. Tritium levels in drinking water are also commonly used in science to date the age of the water in aquifers.
With the confirmation provided by the test results, we hope the public feels reassured knowing the municipal water tested far below the risk level set by the EPA. The safety of Monticello’s residents will continue to be our number one priority. City leaders will continue to share information as it becomes available.