By March 3, 1949, detailed plans and specifications had been canpleted and approved for the first 300-foot tower. The site plans for Parry Island were finally approved on April 8, 1949, but it was August 30, 1949 before definite information was received from JIF-3 about the requirements for Eniwetok Island and a new site plan was prepared. This was approved October 27, 1949. The camp site for Engebi was approved on September 23, 1949; for Runit on October 19, 1949; and for Rojoa on October 21, 1949. The detailed arrangement of buildings for administration and laboratories for Parry Island was developed by conferences at both Los Alamos and Los Angeles between March 31 and May 17, 1949. The animal colony on Japtan was added and basic criteria for it received during conferences at Los Alamos June 30, 1949. The site plan for Japtan Island to take care of the animal colony was approved August 22,1949, With the beginning of the year 1950, the scientific program began to take shape, and throughout the entire year either the Chief Engineer visited Los Alamos or the J-Division representative visited Los Angeles almost weekly. Between visits were many phone conversations, as new Users were included in the tests and as all Users developed their requirements, There were many and frequent changes, and the design departments were kept current by means of these meetings and conversa- tions, Information transmitted orally was later confirmed in writing. The first of a series of instrumentation charts was received fran J-Division on December 13, 1949. These charts gave the identifying mimber, location, a brief description, the User, requirements for power, telephones, and time signals for each station, Revised copies of these charts were issued frequently during 1950 to reflect the current status of these requirements. The H & N Los Angeles office carefully checked each new issue against criteria previously received, and any discrepan- cles or errors were immediately discussed and resolved with the J-Divi- sion representative. In addition to this direct liaison with the JDivision representative, H & N engineering representatives also met with Users and JTF-3 representatives. Some of these meetings were held at the H & N Los Angeles office; others were at Los Alamos, Chicago, Boston, Silver Springs, Md., and Washington, D. C. Such meetings were always with the approval and often at the request of J-Division. As information was obtained, drawings were prepared or revised, material take-offs made, and prints sent to Jobsite. Jobsite personnel were kept advised of changes by teletype as information became available. The information thus transmitted was supplemented by frequent visits to the Jobsite by the Chief Engineer ani members of his division. Without the interchange of ideas and the discussion of problems which this direct type of liaison to obtain design criteria permitted, it would have been impossible for the design and construction of faci- lities to keep pace with the growth and development of requirements which occurred and which had been anticipated in the initial planning for this operation.