CHAPTERIli, SECTION 3 Preliminary Cost Estimates were used as a basis for Construction Budget Submittals, Long Range Reports, and Special Reports and Studies. They were also used for scientific and other types of construction where a general indication of cost was desired. Original Cost Estimates were submitted with requests to AEC for approval of drawings, together with requests for approval to proceed with construction. They were also used as a basis for “Preliminary Proposals” for PAC work which was estimated to cost $20,000 or more. Current Cost Estimates were based on final approved drawings. When these estimates were approved by the AEC, they became the official estimates which were used for computing fee, determining construction progress, and for controlling cost. All of these types of estimates were revised when the scope of work, as defined by the drawings, was changed. a. Under $10,000, at 100% completion. b. From $10,000 to $50,000, at 50% and 100% completion stages. c. Over $50,000, at two-week intervals and 100% completion. In addition, “Special Report Cost Esti- mates” were prepared to reflect the total estimated cost involved for the preparation of special studies and reports as requested by AEC, and “Cost Studies” were prepared to reflect differences in cost for various designs of construction. The latter were prepared primarily to assist Design Engineers and others in the selection of construction methods and designs. The Home Office Estimating Group collected construction progress data from Jobsite, applied weighted values to each item of construction, and computed progress for various PAC pre- projects and expendable construction. These Management to undertake corrective measures, and “S” curves and were distributed to AEC and H&N management for over-all job evalu- Working Estimates and Analyses, pared by the Jobsite Estimating Group, provided a means of job labor control which enabled when necessary. They also acted as an aid to future cost estimating, the establishment of current measurements of actual performance, and the provision of data for use in preparing reports. Working Estimates and Analyses were pre- pared at intervals as follows: 1. 2. Plant Work. Acquisition and Construction a. Under $10,000, at 100% completion. b. Over $10,000, at 33%, 66%, and 100% completion stages. Expendable and Reimbursable Work. progress reports were in the form of bar charts ation. The following table reflects the number of estimates, by type, and their approximate total values: TYPE OF ESTIMATE OR WORK ORDER NUMBER APPROXIMATE VALUE Preliminary 210 $ 38,000,000 Original 915 21,000,000 Current 1,270 54,000,000 419 65,000,000 Working Estimate and Analysis Special Reports 29 400,000 Page 341