Rocky Flats Environmental Technology Site, Highway 93, Golden, Jefferson County, Colorado. Building 121 is located west of Third Street and south of Central Avenue. This building is a primary contributor of the Rocky Flats Plant historic district, and is associated with the U.S. strategy of nuclear military deterrence during the Cold War, a strategy considered of major importance in preventing Soviet nuclear attack. Protection strategies for the Plant included having a highly trained special response team that could respond to actual or potential terrorist incidents, hostage barricade incidents, and other emergencies. Exterior walls are constructed of concrete and concrete block.
Interior walls are concrete, concrete block, gypsum board, and ceramic tile.
The facility has a flat roof covered by neoprene-hypalon and butyl rubber over plastic foam insulation. The windows are fixed, double-panes in metal sashing. The doors are metal. Building 121 is irregularly shaped, extending approximately 100' north-south, 130' east, and 120' west. Building 121 was constructed in 1953 as part of the original plant to serve as the central office building for site security.