Results from routine monitoring tests of the Santa Fe water system’s Buckman well field in 2010 came back with results showing traces of radioactive tritium, but Los Alamos National Laboratory and city officials now say the finding was erroneous.
Final, corrected findings from the tests on three Buckman wells will be posted soon and they will show a “non-detect” for tritium, said LANL environmental manager Danny Katzman.
Alex Puglisi, environmental compliance officer for the Santa Fe water division, said the city also is confident that the non-detect finding is correct, based not only on the corrected findings from the tests performed in August 2010 but also from “multiple lines of evidence” about the well water.
Puglisi and Katzman said the tritium finding reported to the city in March of last year was out of line with previous tests and what’s known about the hydrology of the well field along the Rio Grande west of town.
Puglisi said no tritium was found in subsequent testing on the wells.
“We would never use one sampling event to make a decision” on the wells, Puglisi said.
“If they had seen it (in the 2010 tests), it would persist in the wells,” he added.
Tritium is a radioactive isotope of hydrogen and was produced in the past as part of the production of nuclear weapons.
The original findings by a private lab hired to analyze the August 2010 water samples indicated a tiny amount of tritium in three Buckman wells – between 2.46 and 3.93 picocuries per liter. The federal Environmental Protection Agency’s drinking water standard for tritium is 20,000 picocuries per liter. A picocurie is a measure of radioactivity.
Even though only very small trace amounts were initially reported from the 2010 tests, at issue was whether tritium was somehow finding its way into the drinking water wells – either from the Los Alamos lab, which has historically had tritium on site, or from some other source. Tritium has been found in groundwater near the lab.
Tritium also was prominent in rainfall in decades past when nuclear weapons were tested above ground, according to Katzman.
He said that LANL changed analytical labs in recent years and the results started coming back with different findings than what the previous lab had found over nearly a decade of testing at the Buckman wells. When the tritium findings showed up, the new lab – American Radiation Services International – was “challenged to go back” and review its records and calculations for the low-level tritium tests, Katzman said.
“They actually found errors in what they had been doing,” Katzman said. “The city is aware of the corrections and approved the corrections.”
Katzman said it’s important to check for such low levels of tritium – which is mobile because it is “just water” – because even tiny amounts would be the “ultimate kind of canary indicator of the first arrival of something.”
“A long history of non-detects for tritium is really good news,” Katzman said.