A New Mexico laboratory has detected traces of radioactive material near the Department of Energy's WIPP repository. And while they are well below levels that pose a threat to human health, they do suggest that a small amount of radiation escaped the plant during an incident last week.
At about 11:30 p.m., Friday, an air monitor detected radiation in the underground facility that stores transuranic military waste. The plant's ventilation system automatically switched to filtration mode, according to a release from WIPP (the Waste Isolation Pilot Plant). All employees were above ground at the time and were cleared by radiological control technicians. Nonetheless, the Department of Energy has launched an investigation into the cause of the alarm.
On Wednesday, New Mexico State University's Carlsbad Environmental Monitoring and Research Center confirmed that it detected americium and plutonium near the site. A filter removed Sunday morning from an air sampling station on a WIPP access road collected 0.64 becquerels of americium 241 and 0.046 becquerels of plutonium. Both were found at levels above background but well below those known to be a risk to human health. A second air sampling station on Highway 128 did not show elevated levels of radioisotopes. Nonetheless, the lab noted that the radiation present at the first site was likely from the repository because the sample was taken at the same time as the radiation alarm.