Scientists who monitor the nation's only underground nuclear waste repository say they have detected radiation in the air a half-mile from the site.
Russell Hardy, director of the Carlsbad Environmental Monitoring and Research Center, said Wednesday a monitor near the Waste Isolation Pilot Plant in southeastern New Mexico has detected trace amounts of the radioactive isotopes americium and plutonium.
He says the levels are the highest ever detected at or around the site but are far below those deemed unsafe by the Environmental Protection Agency.
The readings came after a radiation alert over the weekend from an underground sensor at the site.
Hardy says readings will be completed next week on filters collected from that underground sensor and an air monitor closer to the plant.
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