Firefighters work during a controlled burn of grasses and sage brush on a section of land at the Rocky Mountain Arsenal Wildlife Refuge north of Denver in the spring of 2006.

(AP Photo/Ed Andrieski)

A series of prescribed burns are planned at the Rocky Mountain Arsenal National Wildlife Refuge in the northeast Denver area.

The U.S. Fish and Wildlife Service says the fires could begin Tuesday if the weather is favorable. It could take until Friday to complete them.

Officials say the plan calls for a total of less than 1 square mile to be burned. Local and federal firefighters will be on the scene.

Officials say nearby residents might see and smell smoke.

Refuge managers say prescribed burns invigorate the growth of prairie vegetation, control weeds and reduce the risk of wildfires.

The 24-square-mile refuge was once an industrial site that manufactured deadly nerve gas for the military. Later, agricultural chemicals were made there.

A $2.1 billion cleanup was completed in 2010.