RICHLAND, Wash. (AP) - The fire at Hanford nuclear reservation last month churned up radioactive contaminants, including plutonium, but not to levels that pose health risks, the Department of Energy said Wednesday. The plutonium particles were detected in an air sample from a storage area of some of Hanford's most dangerous waste near the center of the 560-square-mile reservation.

The measurement was "well below the level of concern" set by the federal government and the Nuclear Regulatory Commission and did not pose a risk to firefighters or the public, Harry Boston, DOE's deputy manager at Hanford, said at a news conference.

Breathing the measured amount of plutonium for a year would expose a person to 3 millirem of radiation. The limit of exposure for Hanford workers is 100 millirem a year.

Indicators of radioactivity also showed up in 34 of 76 other samples, most of them near the storage areas at the center of the reservation. Those substances could not be determined.

Hanford is the most contaminated nuclear site in the nation after 40 years of making plutonium for the country's nuclear arsenal.