Update on tritium management

Martha Michels

In January, our particle accelerator complex set a new record for beam intensity, delivering more protons for making neutrinos than ever before, exceeding 700 kilowatts in beam power. That is more than twice the beam intensity that we delivered to our neutrino experiments in 2008.

With higher-intensity beams also comes an increase in the production of tritium. I’d like to share with you how we continue to manage tritium at Fermilab and minimize the presence of tritium in surface water, sanitary sewer and air. Water leaving the Fermilab site poses no threat to drinking water.

Tritium, a weakly radioactive isotope of hydrogen with a half-life of 12.3 years, is a normal byproduct of accelerator operations at Fermilab. Very small but detectable levels of tritium are found in the ponds on our site and in the sanitary sewer water that is pumped to a wastewater facility in Batavia. We also measure very low levels of tritium in two of the creeks that leave the site.

These low levels of tritium pose no health risk, and fishing in our ponds remains safe. Tritium does not accumulate in fish or wildlife.

Recent water samples taken from Indian Creek and our eastern ponds show levels of less than 5 picocuries per milliliter (pCi/ml), well below the regulatory standard of 1,900 pCi/ml for surface water we are required to meet. The highest level of tritium found to date in sanitary sewer water is about 12 pCi/ml, far below the regulatory standard of 9,500 pCi/ml.

Every month we report monitoring results in which we find measurable concentrations of tritium to the state of Illinois and the Department of Energy, and the Department of Energy provides an annual report to the City of Batavia, which processes our wastewater. We also share our results with the Fermilab Community Advisory Board, and we post our results on this public website. This website also contains information about the emission of water containing low levels of tritium into the air and the disposal of tritium as solid waste.

We are not satisfied with merely meeting regulatory standards. Fermilab is dedicated to keeping the amounts of tritium produced and discharged from the site as low as possible. Since we first detected tritium in ponds and Indian Creek in 2005, we have put in place many measures to minimize the amount of tritium in surface water and the sanitary sewer. As a result, the tritium levels found today in these waters are only slightly higher than 10 years ago and continue to be well below regulatory limits, even though we doubled our beam intensity.

Still, we want to do better, especially as we plan to increase our beam intensity even more. In summer 2016, we asked Kate Gregory, a member of our Board of Directors, to lead an external group of engineers and experts to review our tritium management efforts. With their feedback,  we created a Tritium Task Force to develop a comprehensive plan to implement the recommendations we received and take additional steps to keep tritium levels as low as reasonably achievable, now and in the future. If you are interested learning more about these plans, please read the report that the Task Force wrote in January.

Though the levels of tritium discharged by Fermilab pose no health risk, we take the matter very seriously and will keep our employees, the Community Advisory Board and the public informed. If you have questions about tritium at Fermilab, please contact the Office of Communication at x3351 or send an email to fermilab@fnal.gov.

Martha Michels is the Fermilab chief safety officer.