Four more workers have now tested positive for radiation after being exposed to a February leak from an underground nuclear waste dump near Carlsbad, New Mexico, the U.S. Department of Energy announced Monday, bringing the total number of contaminated workers to 21.
The announcement came a day ahead of a DOE plan to send a team of experts into the half-mile deep Waste Isolation Pilot Plant (WIPP) to set up bases from which they can begin to investigate the cause of the leak. First detected Valentine's Day weekend, officials later announced that the facility's leak was believed to be releasing radiation into the air.
WIPP is the nation's only permanent underground repository where radioactive waste—including from nuclear weapons production—is dumped deep beneath the earth's surface and stored in salt formations.
Though DOE officials said Monday that all contaminated workers had received "low doses of radiation," well below levels deemed unsafe, they have previously acknowledged that accurately determining dosage requires multiple samples taken over time.
Further, as Robert Alvarez, senior scholar at the Institute for Policy Studies and former senior policy adviser to the secretary of energy under the Clinton administration, recently told Common Dreams, the number of workers exposed was "unusually high."