By Laura Zuckerman
SALMON, Idaho (Reuters) - Firefighters struggled on Thursday to control a 1,000-acre wildfire burning within several miles of a storage area for spent nuclear fuel at a U.S. Energy Department lab in the high desert of eastern Idaho.
Thursday's blaze at the Idaho National Laboratory comes three days after crews extinguished an earlier fire that burned through sagebrush and grasslands on the northwest edge of the 890-square-mile complex, which contains three active reactors.
Lab officials said on Thursday that neither fire posed any risk of radiation releases.
Dozens of firefighters from the lab and from the U.S. Bureau of Land Management were battling the new wildfire, which flared several miles from a facility where spent nuclear rods are stored, according to the lab. Additional radioactive rods are kept cooled in storage ponds further to the south.
"They're fighting it from all directions at the moment; winds are changing every minute," lab spokeswoman Sara Prentice told Reuters.
In addition to conducting nuclear energy research and development, the lab accepts spent radioactive fuel rods from power plants and other sources across the nation.
The nuclear materials are to remain stockpiled at the complex until the federal government develops a permanent storage site for high-level nuclear waste, according to the lab and the Nuclear Regulatory Commission.
Officials said the cause of the blaze is under investigation.
It is one of five wildfires that erupted in eastern Idaho on Thursday amid lightning strikes, high temperatures and strong winds.
Wildfires have charred tens of thousands of acres across Idaho and the Northern Rockies in recent days, including parts of Montana, Yellowstone National Park and northwestern Wyoming.
The National Weather Service on Thursday heightened fire warnings for the region because of soaring temperatures, dwindling humidity and predicted lightning storms with wind gusts of up to 35 miles per hour.
(Editing by Steve Gorman and Jerry Norton)