miles of geophysical trackline can be run per day. Factor e is more difficult 

 to estimate because it depends on three main factors: (a) the vessel speed; 

 (b) mooring time; and (c) the distance between coring sites. On-site time for 

 mooring and taking the cores is usually less than the time spent in moving 

 from site to site. Distances between sites can be obtained from the pre- 

 planned trackline and core site plots. Accurate information on vessel speed 

 and mooring time can be obtained if the vessel to be used has been selected. 

 If no selection has been made, an assumed speed of 5 knots and an assumed time 

 of 30 min for mooring, taking the core, and getting underway to the next site 

 are reasonable planning factors. 



138. Contingency days for weather can be estimated by referring to his- 

 torical sea and swell data summaries such as the CERC Wave Information Stud- 

 ies. Survey equipment is usually reliable; however, a sufficient contingency 

 time of 10 percent of the estimated total survey time should be added to cover 

 the probable delay in replacing system components by air freight. 



139. Costs shown in the sample estimate (Appendix B) are average costs 

 in 1980, and current rates are substantially higher in most cases. 



57 



