CHAPTER II, SECTION 7 paper insulated lead armored cable that had been used in previous installations. Due to the large amount of cable involved with relatively short delivery requirement, it became necessary to spht the order, and approximately 85of lead armored cable and 15+ of plastic covered cable was ordered. As of 23 April 1953 when authorization was received to place the order, 775,000 lineal feet of 16 pair cable was required. Subsequently the deletion of Scientific Stations West of site Tare caused a reduction in these requirements, but the Contractor was authori- zed by the Manager, Eniwetok Field Othce to accept dehvery of the entire order so that it wouid be on hand for possible use at other tocations then unknown, Drawings approved on 30 July i944 indicated that all but 94,000 lineal feet would be required. Another departure from previous test installations was the use of reinforced concrete vaults for housing submarine cable terminals. This cable system was designed for use with several successive tests. These vaults provided for protection against blast effects and a means for ready access to the terminal boxes. They had the further advantage of providing some protection from radioactive contamination for the employees required to work at the terminals between tests. These terminal structures proved entirely adequate as evidenced by the lack of damage atter the various detonations and the few dithcultics encountered in preparing the submarine cable system for each succeeding test. These terminal vaults consisted of reinforced conercte buildings with a gravel floar and a 3’ x 3’ hatch opening. Stations ST 1.1 through 1.3 and ST 2.1 were 8’ x 8 x 7’ high and projected 1°-0° above grade. Stations ST 3.1 through 3.4 were 11’ x 11° x &high and projeccted 2°- 6" above grade. Earth fill was placed on a slope to the tops of the Stations. The location of Station ST 3.3 was on solid coral and the building was constructed on grade. Due to the anticipated high blast pressures, this necessitated the addition of buttresses to this Station which were embedded one-foot into the coral with the reinforcing stcel of the buttresses embedded in holes drilled in the coral. This Station is shown in Figure 2-225. Each of these buildings was equipped with a watertight termina) box for the submarine cable ends and another watertight terminal for the termination of lead covered cables which were run underground to other Stations. Figure 2-226 shows a typical terminal Station with the foundation poured and the sides formed. The system as finally installed consisted of 620,000 feet of 16 pair, 19 gauge sul:marine cable, running in a single systera from site Able to Charhe, thence as a double system around the atoll to Oboe. From Oboe the circuits were completed to Tare via a 51 pair, 19 gauge un- Figure 2-226. S.T. Station - 50% Completed Typical derground cable. The reason for the use of 51 pair underground cable for this run was that the same cable could be used to provide the signal, control and telephone necds of all the islands between Tare and Oboe. This was a more economical installation than providing submarine cable from the control at Nan to Tare and separate cables for all other island needs. Three telephone buuys in the lagoon were connected to the Tare telephone exchange. The signal, control and telephone cable system as finally completed is indicated in the Block diagram Figure 2-227. The actual mechanics of laving of the cables were facilitated by fitting out an LCM as a eahle lacing ahh ang and Amn : eoncis ropa banne TR. ale Anwl awd bottom of this boat were reinforced, a gasoline engine driven winch was installed alongside the wheelhouse and four davits, each carrving a large sheave, were placed along one side of the boat. The cable reel was placed in a special cable dolly in the well deck of the boat, and the cable then run over the winch drum from where it was paid out as the boat moved forward. The cable was laid on a designated course so as to pass over the shortest distance in shallow water between the terminals. For the long run between Nan and Oboe requiring 65,874 feet of cable to be laid in fairly deep water, a helicopter was utilized for assistance in maintaining the proper course. Figure 2-229 shows men laying cable in shallow waters from a terminal station. The changes effected in laving interisland cables for the CASTLE OPERATION are summarized as follows: (1) Cables were gener- Page 2-228 ee ent thse tae BA cn DI eat ‘pagal aT hate3 we? aed wnt lt oj