The exploration phase usually lasts from 1 to 7 years (New England River 

 Basins Commission 1976a). Temporary service bases are established, generally 

 locating in existing ports to serve and support exploratory drilling. Explor- 

 atory drilling is conducted from a jack-up platform, semi-submersible plat- 

 form, drill ships, or barges. Limited onshore support activities are required 

 during the exploration phase and most of this activity is temporary, often 

 operating on leased space. One of the most important onshore activities dur- 

 ing exploration is support from service bases and from suppliers of tubular 

 goods and drilling muds and cement. 



The development phase lasts from 4 to 9 years (New England River Basins 

 Commission 1976a) after which oil and gas are produced commercially. Develop- 

 ment drilling is usually performed from fixed platforms that are floated to 

 the site and position on the ocean floor. Onshore activities peak during the 

 development phase. Permanent service bases are established, oil /gas transpor- 

 tation systems are implemented, and a diverse assortment of industries (such 

 as tool and equipment companies, catering services, repair and maintenance 

 yards, diving companies, and specialized drilling equipment companies) locate 

 onshore. 



As well drilling is completed, the production phase begins. This phase 

 lasts 10 to 25 years or more. During this phase, the drilling is disassembled 

 and production equipment is installed. Oil may be pumped ashore by pipeline 

 or pumped directly into tankers. Volume production and demand will dictate 

 whether OCS oil and gas production near Florida will be refined in Florida or 

 trans-shipped out of the State. Gas must be piped to shore for processing and 

 treatment facilities, but a gas processing plant may be constructed inland 

 between the OCS pipeline landfall and the existing gas infrastructure (distri- 

 bution system). 



During shutdown in a field, onshore facilities and operations would close 

 or shift to other uses. 



LOCATION FACTORS FOR ONSHORE FACILITIES 



Proximity to offshore OCS activities is generally the most important fac- 

 tor in determining the location of onshore facilities. Another important con- 

 sideration is the tendency for OCS support activities to aggregate, or locate 

 in a central geographical area, usually in a port area. The tendency to clus- 

 ter near other related industries would meet the need for cooperation and in- 

 teraction among the support activities. Economic efficiency may be achieved 

 by minimizing the duplication of facilities and equipment. 



A number and diverse assortment of onshore support facilities are 

 required to support offshore OCS operations. Some of the major factors 

 affecting the number and location of these facilities are listed below (New 

 England River Basins Commission 1976b). 



Location of oil and gas field 

 Size of oil and gas field 

 Topography of oil and gas field 

 Depth of water 



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