Figure 8 Post 18 at Sandia Canyon Site (TA-20), 1948
Related Figures (44)
Map 1: Manhattan Project National Historical Park boundaries at LANL The Laboratory opened its wartime Security and Pass Office, located within the main technic: area (TA-1), in April of 1943 (Figure 1). Security functions included safeguarding classified information and investigating new employees. The World War II-era Security Office supplied guards for classified shipments, couriers for documents, and guards for convoys. The Security Office was also responsible for incoming shipments and made the arrangements for meeting these shipments as well as safeguarding and delivering them. In order to safeguard classified information, the Security Office issued document classification and handling instructions. The issuing of security clearances, also arranged by this office, was often a lengthy process. This background investigation, however, was a requirement for assignment or employment at Los Alamos for both military and civilian personnel (Truslow 1991). Figure 2. Los Alamos main gate Special nuclear materials and the associated technical and scientific operations were under the direct oversight of the Security Office. Due to the expense and military importance of these special materials, they were placed under continuous armed surveillance by a dedicated detail of military and civilian guards. Other areas of responsibility included the guard system, visitor control, and the pass system. Physical components of the guard system included main guard posts placed at key entrances to Los Alamos and at entrances to TA-1 (Figures 2 and 3). Other guard facilities were also established at outlying technical areas (Truslow 1991). Figure 3. Los Alamos main gate, 1940s The early Los Alamos townsite was a fenced community that resembled a military post. The main technical area, which started actual operations in early 1943, was fenced and separated from the rest of town and only specially badged workers were allowed inside the guarded laboratory area (Figure 4) (Hawkins 1983). Similarly, the outlying technical sites south of TA-I1 required specific access passes. Figure 4. Security check point, TA-1 Figure 5. Guard shack in use as public telephone building, Los Alamos townsite. Note the mounted skids below the doorway designed for ease of transportation. The stovepipe penetration is located in the left rear of the structure. Figure 6. TA-1 with security fence. juard shack is located in center right of pho During the Manhattan Project, guard shacks were moved over a wide geographic area. For example, two guard shacks located at TA-18 (Pajarito Site) were previously located many miles away. Guard shack TA-18-111 was moved from TA-27. Guard shack TA-18-112 was previously located at TAs 16 and 15. Elsewhere at the Laboratory, guard shack TA-16-160 was moved from TA-16 to TA-33 and then back to another location in TA-16. Guard shack TA-4-9, originally located at TA-4, was moved to TA-0 and then to TA-16. Guard towers were moved as well. A guard tower originally located at TA-1 was moved to TA-18. Figure 9. Post 18/Station 104 in 2003 In 1943, a group of Los Alamos scientists under the direction of Emilio Segré established a smal. laboratory in Pajarito Canyon to study the chemical properties of the new man-made element plutonium (Figures 10 and 11). The work conducted at Pajarito Site by Segré’s Radioactivity Group led to the abandonment of the plutonium gun-type design in July 1944 (MED 1946:VL-8, VI-9). Soon after, as the development of the plutonium implosion weapon drove the need for new testing areas, firing sites were built at Pajarito Site to study high-explosives shots using the magnetic method. Figure 10. Emilio Segré’s Radioactivity Group Figure 11. Radiography Group facilities at Pajarito Site, circa 1943 By the fall of 1944, Segré’s group had moved to the East Gate Laboratory site located away fron the hustle and bustle of Pajarito Canyon, which now had a new mission related to the development of the implosion weapon (Figure 12). According to the official Project Y history produced shortly after the end of the war, the move was a beneficial one for the Radioactivity Group: “This change had the advantage of a much shorter commuting distance, and also of avoiding close contact with new high explosive firing sites, as the test area of the implosion program expanded toward Pajarito Canyon” (MED 1946:XII-3). East Gate Laboratory, also known as TA-19, was specifically established for use by Segré’s group to study spontaneous fission measurements. The technical area was located away from TA-1 in downtown Los Alamos because of the sensitive electrical equipment used by the Radioactivity Group (Figures 13, 14, and 15). The East Gate Laboratory site, inadvertently developed just outside of Project Y’s eastern property boundary, was surrounded by a fence ar included a main laboratory building, a small instrument or shelter building located adjacent to the main laboratory, a battery building or storage hutment, a guard building, a retreat building, and a latrine. Built during the summer of 1944, the site was active after the war until the 1960s (LANL 1992:3-8, 3-9; The Director 1947). Figure 13. East Gate Laboratory main building, February 27, 1958 Figure 14. Interior view of Segré’s laboratory building, circa 1945 Figure 19. TA-8-172 at its location in TA-21 Figure 20. TA-8-172 being placed at TA-8 Figure 21. TA-8-172 at its TA-8 location Figure 24. A portable Manhattan era guard station, TA-18-111, located in Bandelier National Monument. The building features a gable-style roof, rabbeted shiplap siding, and six-pane divided light windows. Figure 27. Historic photo of TA-20-20. Figure 30. Exterior of TA-20-20. Note the historic keyless light fixture and surface mounted wiring installed underneath the gable roof. Figure oc. Neverse VIEW OT 1 A-cU-cu. Note the presence of a single, nine-pane divided light window located along the side of the guard station View of south side (2011) Architectural Description: Guard shack TA-8-172 is a single-story, square-in-plan building measuring 7 ft x 7 ft x 7 ft 8 in. high on the low side of the sloped roof and 9 ft 2 in. at the high side of the roof with a finished interior square footage of 38.5 ft?. Constructed of 2 x 4 wood frame construction, the interior of the building is sheathed with sheetrock. The floor is covered with layers of plywood with remnants of laminate flooring on top. There is some evidence of mineral wool insulation present. The electrical system is surface mounted in conduit, and has one fourplex receptacle over one twoplex receptacle. The building featured a woodstove in the back left corner and a telephone shelf on the right back corner. Buildings with same floor plan within other TAs: None TA-8-172, front and right sides TA-8-172, right side TA-8-172, left and front sides TA-8-172, back side TA-8-172, back left sides and roof
