CHAPTER I!, SECTION 3 adjacent wall of the shelter opposite. The interconnecting wall was framed of horizontal wood girts with plywood sheathing between Elevation +16.0 and the roof level of the shelters. A level pattern of 5-foot-wide by 2-foot-high openings were provided in the south shelter walls and interconnecting walls facing Station 1522 and centered at Elevation ~28.0. The south surfaces of this entire structure were painted black. Each shelter structure was furnished electric power from an island transformer station, telephone, STATION: 1525 SITE: Irene USER: LASL PURPOSE: Fluor Station and Mirror Tunnel PARTICIPATION: 21 DESIGN PSI: None field phone, signal cabinet, lighting, and con- CONSTRUCTION: 1-22-58/4-15-58 STATION: 1524 SITE: Irene This station consisted of a re-inforced concrete Fluor Station with a wood frame lighttight tunnel connecting to Station 1526. The Fluor structure only was earth-barricaded to USER: LASL PURPOSE: Camera Stand Station venient outlet receptacles. PARTICIPATION: 21 DESIGN PSI: 70 psi CONSTRUCTION: 1-8-58/ 4-25-58 Station 1524 occupied Room 4 of RED- WING Station 1611. The room was 24x15 feet in plan with a 9-foot ceiling height. The floor slab was 324 feet thick, walls were 4 feet thick, and the roof slab was 314 feet thick, all of heavily re-inforced concrete construction. The room was copper screened on walls and ceiling; it contained two electric heaters, a dehumidifier unit, light fixtures, convenience outlets, and a camera stand. The camera stand was a steel frame, 24 feet Jong by 2 feet wide by 2 feet high, with a 24x14-inch aluminum plate cover 24 feet long. Five existing buried 24-inch-ID steel pipes extended from a port opening in the west wall of the station through an existing retaining wall. The overall length of the pipes was 25 feet. The existing fill over the pipe area extended from a 10-foot-deep fill, top of fill Elevation + 26.5, to the top of the retaining wall at Elevation ~ 18.0, This fill area was raised over the top of the wall Jevel to barricade Station 1526 to Elevation — 23. Wing walls of the existing retaining wall were removed to provide a straight wall section 50 feet long. This wall section then provided the east wall of new Station 1526 and a portion of the east wall of new Station 1311. At the west end a depth of 5 feet over the roof slab. A single room space, 1314x114 feet, with a 614-foot ceiling height was provided by the Fluor struc- ture. The floor slab was 114 feet thick: the front wall facing Station 21 was 5 feet thick; other walls and the roof slab were 2 feet thick. A reinforced concrete breast wall, 3714 feet long, was shaped around both sides of the front wall, rising to 3 feet above the roof slab. Fill against the front face of the breast wall was shaped to provide a V-shaped cut opening to a 36-inchdiameter pive sleeve in the Fluor structure front wall on a line-of-sight to Station 21. A 6-footwide by 514-foot-high tunnel section 10 feet long with 12-inch thick re-inforced concrete walls, floor, and roof slab extended from the Fluor structure south wall and connected to the end of the wood frame tunnel to Station 1526. The tunnel was 152 feet long, of wood stud and joist frame construction over a combined floor and footing concrete slab, and contained plywood sheathing over wall and roof framing. Wood frame tunnel sections were 3214 feet long by 7 feet clear inside width, 50 feet long by 8 feet clear, 50 feet long by 9 feet clear, and 1914 by 10 feet clear. The average clear ceiling height of the flat slope roof joists was 734 feet. Four light-tight louvered 3x7-foot access doors and twenty 3x34x5'%4-foot light-tight louvered vent wall panels were installed in the length of the wood framed tunnel. The structure contained utility and experimental electric power panels, signal panel, field telephone, lights and convenience outlets. STATION: 1526 SITE: Irene USER: LASL PURPOSE: Mirror House of the five 24-inch pipe sections, on the east wall of Station 1526, a heavy pneumatically operated steel guillotine door was installed and connected to the signal system for closing during use. A 4-inch helium exhaust pipe extended from 24-inch pipe into Station 1526 and up through DESIGN PST: the camera stand through the most southerly the station roof. Page 106 PARTICIPATION: 21 None CONSTRUCTION: 1-8-58/4-16-58

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