Benthic communities , which are important as a commercial resource (clams, 

 scallops, oysters, shrimp, crabs) and as a food source for important finfish 

 and shellfish species, will suffer significant adverse effects but probably 

 on a localized scale. Activities of greatest potential impact will be: 



a. construction of pipeline corridors and burial of pipes; 



b. emplacement of platforms; 



c. deposition of drilling wastes near the platforms. 



As many as 3,000 acres of benthic habitat could be affected by platform 

 construction and operation, while pipelines will require a several -hundred-foot 

 swath from the platform to shore. Drilling wastes may impact benthos by form- 

 ing mounds near platforms several hundred feet in diameter and several feet 

 deep, causing sessile organisms to be lost. Increased turbidities associated 

 with pipeline burial and drilling waste disposal will further impact the ben- 

 thos as well as all other local marine communities. Effects of small amounts 

 of oil, hydrocarbons and heavy metals in the drilling wastes on the benthos 

 has not been well established and may be negligible. 



Recolonization of disturbed sediments will take place rather quickly 

 (probably between 3-6 months) along pipelines and other areas which are not 

 regularly disturbed by such activities as discharge of drilling cuttings. 



Impact on zooplankton and phytoplankton communities may stem from 

 oil spills, discharge of drilling muds and formation waters, and from 

 turbidities caused by pipeline burial activity. The offshore plankton 

 communities are less concentrated than those in the bays and nearshore 

 areas (4:3, p. 279). Thus, a spill in the production area would likely 

 cause less damage than one in the estuarine zone. Turbidities would be 

 caused by several factors previously mentioned, but especially by drilling 



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