bulkhead was provided on the lagoon side only, The width was necessary for the construction of a 12-pipe array and to provide room for an access road. The bulkhead was. constructed by driving 60-pound used rails on four-foot centers which were horizontally backed up by three-inch thick timbers. was then earth filled to provide the dimensions indicated above. This An earth-filled causeway 1100 ft. long between Reere and Eninman was constructed to provide the necessary zero line length required for Station 50. This causeway was 60 ft. wide so as to provide for construction of a three-pipe array, a 24 ft. access road, and a right of way for telephone and signal cables. Adequate protection was provided by riprap which was readily bulldozed in place from the adjacent reefs. In order to locate certain scientific installations 7500 ft. from Station 20, as required by the test program, it was necessary to construct an earth-filled island approximately 700 ft. west of Bokobyaadaa, This island, designated site Delta, was slightly over 0.5 acre in area and was built to an elevation of + 8.5 ft. MLWS. The perimeter was bulkheaded with three - inch width timbers supported by 60-pound used rails driven on four-foot centers without tie-rods. This island was connected to Bokobyaadaa by an earth-filled causeway to provide access to the site. To provide for the zero line for Station 60 and the installation of the two-pipe array from this station, it was necessary to widen the existing access road between Eberiru and Aomon to 60 ft. Bulkheading was not originally provided, but during a storm in November 1953, the wave action caused sufficient erosion to threaten the pipe supports. To remedy this condition, bulkheads on both the lagoon and ocean sides of the causeway of the type previously discussed were installed. To provide access roads to construction sites on the Yurochi and Aomoen group, the islands were connected as follows; Yurochi - Uorikku - Approximately 3000 ft. of causeway Uorikku - Romurikku - Approximately 1200 ft. of causeway Romurikku - Aomoen - Improvement of connecting reef to permit vehicle traffic Available bank and reef coral was used and the surface traffic-compacted. The causeways were finally built witha width of 25 ft. at an elevation of +8.5 ft. MLWS. During high tides the Romurikku-‘Aomoen road became inundated, but not sufficiently to stop traffic. Land access from Eninman to the islands eastward to Airukiiji was a nec- essity for economical construction and operation of facilities and scientific stations located in this group of islands. Bank and reef coral was usen when available, and the surface was traffic-compacted. The access road between Airukiraru and Airukiiji later became a part of the airstrip built on these islands, and the reef between Reere and Eninman was utilized in the construc- tion of the causeway to carry the pipe array for Station 50 which was previously discussed. These access roads were finally constructed so as to pro- 57