Some residents are concerned that low-level nuclear waste stored above ground could produce radioactive smoke if the fire reaches the facility.
The fire has grown to more than 108 square miles, as firefighters brace for more erratic winds.
Crews have managed to hold lines along the southern boundary of Los Alamos National Laboratory as well as along a highway on the edge of the community of Los Alamos.
The fire is threatening a dump site with 20,000 barrels of waste contaminated with plutonium. Lab authorities say they're taking every precaution.
"We've removed fuels from near the buildings. We've done the analysis to understand what would happen if a fire occurred. And we've made plans to deal with that," said Charles McMillan, director of the Los Alamos National Laboratory.
The blaze has torched 30 buildings in the New Mexico countryside and forced the evacuation of Los Alamos, a town of 11,000.
The Associated Press contributed to this report.