CHAPTER !1, SECTION 3 Figure 2-35. STATIONS: PURPOSE: SITES: USER: 18 and 19 Ground Zero (Airdrop target) 18 Charlie, 19 Yvonne LASL CONSTRUCTION: Station 18, 2-23-56/4-2556; Station 19, 6-10-566-15-56 At the site of Station 18, the ground was leveled, white sand was spread, and concentric black rings were provided by spraying with an asphaltic emulsion. The rings were 20’ wide, with the exception of the inner ring, which was 30’ wide. The outside diameter of the largest ring was 440’ and the inner rings had outside diameters of 340’, 240’, and 100’ respectively. Station 19 requirements were similar to Station 18, except that the diameters of the concentric rings were smaller; the outside ring was 310’, the two inner rings were 210’ and 100’, respectively. It was necessary to extend the rings over buildings that were located within the marked area in order to provide a contin- uousring. Page 2-52 Station 18 Located at the center of each target was a 50 foot creosoted wooden pole set in a 4’x4’x6’ high concrete footing. A 500-watt clear lens beacon with flasher and a fused disconnect switch were mounted on top of each pole. Power for Station 18 was provided from Station 7412; Station 19 was supplied from Station 7413. STATION: PURPOSE: SITE: 22 Ground Zero Tare USER: UCRL CONSTRUCTION: 10-25-56 5-23-56 OCCUPANCY: 4-10-56 This station was a steel frame building 40’ x 27’ x 31’ high built on a concrete slab foundation. Three walls and the roof were covered with corrugated aluminum. The 27’ long 36’ high east wall was of reinforced concrete 3 feet thick. This wall contained blockouts ‘through which the 90’ and 300’ pipe arrays of Station 2310 were grouted. Two reinforced concrete wing walls 21’ long, 32’ high, and 3 feet thick extended from the sides of the front wall at