The Bay Area Rapid Transit (BART) project involves construction of 

 large concrete conduits on the floor of San Francisco Bay. This project 

 has served to establish, to a certain extent, underwater construction 

 techniques at shallow depths (160 feet) . 



APPROACH 



The SEACON experiments are to be carefully chosen, integrated and 

 time phased. Where feasible the major developments will be tied together 

 so that they provide visibility of total capability and allow integration 

 of different technologies. However, in cases where this is not feasible, 

 separate experiments are planned. 



A number of experiments which will push the state-of-the-art are 

 described. While interrelated to the extent that they would or could all 

 contribute to placing a complex installation on the ocean bottom at great 

 depth, they are designed and implemented in such a way that failure of 

 one experiment will not jeopardize the overall experiment. Their inde- 

 pendence will also provide the necessary program flexibility to allow 

 expansion or reduction of the SEACON experimental program with availa- 

 bility of project support. 



The RAVFAC portion of the DOT project is primarily directed toward de- 

 veloping seafloor construction technology at depths greater than diver cap- 

 ability. Therefore, the main emphasis in SEACON is on developing non-diver- 

 assisted techniques. 



At the conclusion of major portions of the experiment, a report will 

 be prepared evaluating the overall program. Where appropriate, individual 

 reports will be prepared in detail on the results of specific experiments. 



PLAN 



Depth and Location 



SEACON will be at a depth of about 600 feet. Shallower depths would 

 not adequately push the state-of-the-art, but greater depths would pre- 

 clude the effective assistance of saturated divers if required. The 

 600-foot depth is also generally considered about the edge of the con- 

 tinental shelf, and any capability demonstrated for that depth would be 

 applicable for most of the shelf. 



SEACON will be located near Port Heuneme, California, close 

 to most of the ocean engineers and scientists involved and to its 

 primary soiirce of logistic support. Costs should thereby be 

 reduced and time saved. The choice of the exact site will have to take 

 into account its potential availability and the conflicting requirements 



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