• Sandia National Laboratories Technical Area II Historic District

    Between 1948 and 1952, Tech Area II was the primary assembly site for America's nuclear weapons.
    The area was designed and constructed in 1948 specifically for the assembly of the non-nuclear components of nuclear weapons, and both the architecture and location of the early buildings in the district reflect their original purpose.

  • 1951 plot plan of Area II. Buildings 904 and 907 (the two large buildings located on the north-south axis of the area) are approximately 1,100 feet apart.

    Site of Technical Area II

    Tech Area II was a diamong-shaped piece of land of approximately 45 acres located about 1/2-mile south of Sandia's Tech Area I on what is now Kirtland Air Force Base near Albuquerque, New Mexico. It was surrounded by a 10-foot high chain link fence, with one guard tower standing outside the gate at the western point of the area and additional guard towers at each of the other points of the diamond.

  • The Kruger firm's impression of the site

    Vision of the Site

    The architectural firm of W.C Kruger and Associates was brought in to design the facilities for Tech Area II. The primary buildings were Building 901 (the Change, Break, and Laundry Room) and Buildings 904 and 907 (the assembly facilities). There was also a guard house (Building 900) and guard tower (Building 909) at the area's entrance at the west point of the diamond. Buildings 903 and 908, the mechanical rooms for Buildings 904 and 907, respectively, also date from the initial 1948 construction, as does Building 902 (the Standby Power Generator).

  • Guard tower and guard house at entry to Tech Area II

    Guard Tower

    The guard tower (Building 909) was built outside of the western point of the diamond-shaped parcel that formed Tech Area II. A guard house (Building 900) was also constructed at the entrance to the site, sitting at the food of the tower.

  • Looking east from the guard tower at the entrance to TAII

    View from the Top

    Building 901 (the Change, Break, and Laundry Room) was just east of the area's entrance. Building 904, one of the two assembly buildings in the area, was at the end of the road heading out to the southeast.

  • View of front (west) wall of Building 901 extending as a retaining wall and the earth covering the building.

    Building 901 Exterior

    The amount of high explosive handled in the assembly area was the primary concern in architectural design. The front (west) exterior wall of Building 901 (Change, Break, and Laundry Room) extended in wings to the north and south and along the top of the building to provide a retaining wall for the earth covering the building. This provided blast protection from the two assembly buildings located to the building's east.

  • Architect's conception of Building 904

    Building 904

    The assembly buildings (Buildings 904 and 907) were designed to house the linear movement of items through the assembly process. Components and sub-assemblies entered the building at the low end and moved along as they were assembled into weapons, finally reaching the high-bay at the opposite end of the building. From there they exited the building and were sent to storage.

  • Building 904 in 1948

    Building 904 Housed Assembly Activities

    Buildings 904 and 907 housed the weapon assembly activities. Subsystems and components assembled or purchased elsewhere entered the buildings at their lower ends and moved through a series of assembly bays until they reached the high bay at the building's opposite end.

  • Building 907 in 1948

    Building 907

    Buildings 904 and 907 were built as mirrors of one another. To the southeast and northeast of the change building (Building 901), they were aligned along the north-south center line of the area, with their low ends approximately 1,100 feet apart.

  • Building 907 floor plan

    Built to Handle Explosives

    The original floor plans of Buildings 904 and 907 indicate how the assembly process worked. They also reflect the risks of handling high explosives. Note in particular the narrower rooms with no openings between the larger assembly rooms. These were rubble-filled rooms meant to buffer and collapse onto the rooms next door in the case of an explosion.

  • Concrete west wall of rubble-filled buffer room extending into the corridor in Building 907

    West Wall Extends Into 907 Corridor

    The west walls of the narrower, rubble-filled buffer rooms were apparent in teh buildings' north-south corridors. The concrete west walls extended approsimately 10 inches into the corridor.

  • Formerly rubble-filled buffer room in Building 904

    Formerly Rubble-Filled Space in Building 904

    In the years since weapon assembly ended in Tech Area II, modifications to the buildings included opening up one of the rubble-filled buffer rooms in Building 904 to use for storage. The wall between this room and the assembly room next door is 2 feet thick. The interior walls of teh buffer room lean outward as they go up, a design meant to encourage the collapse on the neighboring assembly rooms in the case of an explosion.

  • Explosion-proof light fixture in Building 907 high bay

    Spark-Resistant Fixtures

    The original fixtures in the buildings were “explosion-proof,” meaning spark-resistant. Telephones were heavy, sealed Western Electric units that allowed no sparks to exit the casing; light figures were similarly heavy-duty, with thick glass reducing the chance of sparking and metal cages protecting them from breakage.

  • Sketch map of Tech Area II layout in 1998

    Post-1952 Activities

    Weapon assembly continued in the area after 1952, but the major responsibility for assembling War Reserve, or stockpile, weapons shifted to other sites in the Atomic Energy Commission's (AEC) integrated contractor complex. Eventually, Sandia's assembly responsibilities ended and the Lab moved its explosives research activities into Tech Area II. Additional buildings were added over time.

  • Storage igloos along the northwest perimeter of Tech Area II in 1998

    Expansion of Facilities

    A variety of different structures were added to the area over time, including storage igloos for explosives and other materials.

  • Metal storage igloo with front wall extending to serve as a retaining wall for the earth blast berm that covers the structure

    Storage Igloos

    The storage igloos were standard military designs, meeting specifications for explosives storage.

  • Building 907 Converted

    In addition to increasing the facilities in Tech Area, the Lab also modified the existing structures. Building 907 was converted to explosives testing, with test pads added to the exterior of the east side.

  • Rooms with Multiple Views

    Tests were controlled from the building's interior, with heavy glass and steel ports allowing observation and data capture.

  • Top of the guard tower, 1998. The tower had not been used for several decades by this point.

    Aged Guard Tower

    The facilities were aged and difficult to maintain by the 1990s and more efficient facilities were under design to house explosives testing.

  • Building 907 in 1998

    The End of the Area

    In 1998, the Tech Area II facilities were slated for demolition. Per agreement between the U.S. Department of Energy, the New Mexico State Historic Preservation Officer, and the Advisory Council for Historic Preservation, the historic district was documented prior to demolition.