CHAPTER |, SECTION 1 and navigable channels were swept from these passages to practicable ship anchorages in the lagoon. When explored, most of the islands had a dense ground cover of vines and brush, as shown in Figures 1-1, 1-2, 1-10 and 1-11. Occasional trees were found, some 85 feet in height. The ground surface is generally flat, of coral sand and has an average elevation of less than ten feet above mean lower tide. With the exception of a few beaches, approaches to the islands by landing craft were not possible without dredging, due to the presence of a flat, shoal, coral-studded shelf, typical of atoll conformation. on the innerside of Bikini Island (site How). Bikini Island, the largest in the Atoll, is approximately 2.1 miles long by 0.5 miles wide at the widest point. A dense growth of palms and ground vegetation covered the Island. It had been used in 1946 for the base camp of OPERATION CROSSROADSand a few frame and canvas structures were found. Several concrete slabs still remained as did some supplies and equipment such as gasoline, diesel fuel, anchors and chain, dragline buckets, old stills, etc.; some of these items were salvable. Bikini Atoll is situated in an area domi- The original study was predicated upon the use of Eniwetok Atoll as a supporting base for the Bikini Atoll Auxiliary Proving Ground The mean wind velocity is 9.6 knots, 44% from plated tests, the following minimum Bikini facilities would have to be provided: nated by the northeast trade winds, and weather conditions are comparable to Eniwetok Atoll. the east and 34% from the northeast; the mean cloud cover is 4.1%; and the Atoll has an aver- age of 14 rains per month with a total annual average of 81 inches. _ The mean tide range is 3.0 feet, the mean high water spring tide rise is 5.5 feet, and mean low water spring tide is 0.6 feet. _ It was determined that the best anchorage with shelter from the prevailing northeast winds was located about 1,400 yards from the beach Figure 1-2. Page 1-2 but assumed that, to accomplish the contem- A port-of-entry base camp to accommodate a total population of 250 men on Bikini Island. A shot island camp for each experiment to accommodate 500 men. An airstrip at the base camp suitable for C-45 and C-47 airplanes. Liaison airstrips (minimum length feet) on each group of shot islands. Typical Island Vegetation - Bikini Atoll 1200