CenterPoint Zimmer LLC is building the complex for the U.S. National Nuclear Security Administration.
The NNSA has a contract with Honeywell Federal Manufacturing and Technologies to operate the new facility, which will supply 85 percent of the non-nuclear parts comprising a typical nuclear armament, The Kansas City Star reported.
While the new complex isn't scheduled to be online until mid-2014, the federal government has begun making lease payments to the private landlord of the plant nearing completion in southern Kansas City.
The new 1.57 million square-foot facility will create 2,500 jobs while replacing a former World War II-era defense plant.
The NNSA estimated that the new facility will result in savings of $100 million annually in operating costs because it has a more efficient design than the outmoded factory.