All processes and operations are continuously monitored by the 

 platform crew. Their sole functions are maintenance and emergency 

 control. Valves to regulate the flow of hydrocarbons can also be 

 controlled by radio from shore or a nearby platform. 



A well may yield combinations of oil, gas, water, sand, and other 

 materials from the productive horizon. The purpose of the automated 

 treatment equipment on the platform is to separate these materials for 

 shipment ashore, reinjection back into the reservoir, or disposal. At 

 high formation pressures, most natural gas associated with oil is in the 

 liquid form. A separate pipeline is justified only if there is a 

 significant recoverable quantity. In that case, the oil and associated 

 gas will be separated. The gas may be processed on the platform to 

 further remove water and other undesirable components such as hydrogen 

 sulfide. However, if the quantity of gas produced is so small as not to 

 warrant the construction of a separate pipeline, then a single pipeline 

 would be used to transport both the oil and gas to shore. If the quantity 

 of gas is limited, in many cases the gas will be reinjected back into 

 the wells to maintain reservoir pressure to force oil to the surface; it 

 may also be used as a platform fuel. 



Workover is a periodic operation to improve well production by 

 modifying downhole conditions (caused by sanding of wells and decline in 

 pressure). This operation, requiring crews and equipment including a 

 derrick, is usually conducted approximately ten years after initial 

 start-up (or when a well has production problems) and includes operational 

 and procedures similar to initial well-drilling. 



A workover involves the removal of sand, water, and any other 

 substances which may accumulate in a well during production. During 

 workover operations the casing may be perforated at different depths to 

 bring in a new producing zone. In addition, safety equipment together 

 with any artificial pumping apparatus is removed for inspection and 

 overhaul before being reinstalled. Generally, during workover operations, 

 the wells immediately adjacent to the well being worked on will also be 

 shut down for safety. 



Community Effects 



The major effects of platform installation and operation are: (1) 

 increased local employment relating to onshore facilities; (2) increased 

 waterfront industry and general commerce. 



Employment : A platform operation has two major phases with different 

 employment characteristics. Highest employment occurs from the time a 

 platform is first placed offshore until the last well is completed. 

 After completion, the operation of wells under the platform is monitored 

 by a much smaller work force. Estimates of platform employment during 

 production drilling vary from 65 to 217 workers. After the wells are 

 drilled employment drops to an average of 16 employees [25]. 



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