I would be interested to know what concentrations they are finding; although, from my 30 years of work experience in the environmental health field, I know that tritium is found in many drinking water supplies, in very low levels, and can be used as an indicator of relatively recent aquifer recharge. The presence in groundwater is due to the prevalence of hydrogen bomb testing in the 1950’s or so, which put this form of hydrogen in the atmosphere. It is not considered a contaminant of concern at these low levels, but more more of a helpful tool to age-date groundwater.
I agree with other posters who have a problem with the fact that that Xcel and the state agencies are just coming clean now when they knew of the situation in November. It’s no wonder people are distrustful of large industry and government.
Half life of tritium is 12 years. The 1950s were at least 5.58 half lives ago. Tritium was released during atmospheric thermonuclear weapons testing has decayed to at most 0.021 of its original amount.
Tritium is formed in the atmosphere by cosmic rays interacting with hydrogen in water molecules.