Building History Click image for low-res file   CO-83-U-1 – Aerial view of Building 991, looking west. Building 991 was designed for shipping and receiving and for final assembly of weapons components. (6/26/91) (Hi-res [300 dpi]) CO-83-U-2 – View of interior of Building 991 loading dock area. The dock provided a covered shipping area specifically designed for the safe secure trailers that were used to ship production materials. (6/11/87) (Hi-res [300 dpi]) CO-83-U-3 – View of integrity-testing equipment using cryogenic baths in Building 991. (6/7/68) (Hi-res [300 dpi]) CO-83-U-4 – View of ultrasonic testing equipment in Building 991. This equipment nondestructively tested weapons components for flaws and cracks. (9/11/85) (Hi-res [300 dpi]) CO-83-U-5 – View of the heating elements and vacuum gauge of a pump-down station in Building 991. The pump-down station removed out-gases from inside the triggers. (9/26/61) (Hi-res [300 dpi])