The Interior Department is on the road to creating its own unmanned drone air force to conduct the higher-risk work of the agency at lower cost.

The agency on Monday awarded Berkley, Calif.-based 3D Robotics a $256,000 contract to build 40 three-pound unmanned aerial drones customized for the agency's specific needs.

The deal is hoped to be a cost-cutting measure, said one senior Interior Department official.

"These [drones] will not only provide us with better science and reduce the risk to our employees, but they will result in cost savings and better service for the department and the American people," said Mark Bathrick, the director of the agency's office of aviation.

Bathrick expects to use the unmanned drones for a "set of missions" that include fire management, wildlife and vegetation surveys, search and rescue, hydrologic study, cultural resource inventory, and surface mining monitoring.

The drones will replace the need for manned aircraft flying potentially-hazardous missions at increased cost.

"The contract is extremely important to the department, as it will allow us to conduct many missions that were previously impossible due to limited resources and costs associated with using manned aircraft," said Harry Humbert, the agency's deputy assistant secretary for emergency services and public safety.