CARLSBAD, New Mexico (AP) Crews investigating a radiation leak at the U.S. government's underground nuclear waste dump in New Mexico have turned up no contamination during a second trip farther into the half-mile(kilometer)-deep repository.
The Department of Energy says Friday's trip at the Waste Isolation Pilot Plant allowed crews to establish a base where they can safely remove and store their clothing and equipment if it becomes contaminated.
The crews also set up more air monitors and tested communication equipment.
A third trip to find the leak's source is expected next week.
The repository has been closed since mid-February, when the leak sent low levels of radiation into the air and contaminated 21 workers.