Construction : With the need to lay a pipeline to shore, most of 

 the environmental impacts will arise from the dredging needed to bury 

 the pipeline. (Section 2.2.4) Dredging of pipeline trenches, especially 

 in coastal areas should be done in a manner which will minimize turbidity 

 and sedimentation (such as the employment of sediment screens and other 

 techniques). If pipeline trenches are dug through wetlands, excavated 

 material should normally be replaced in the trench instead of diked 

 along the sides where it can interrupt water flow and change circulation 

 patterns, salinity, temperature and other factors. Also, fill material 

 should be added incrementally where necessary, not all at once, in order 

 to keep the elevation above the pipeline the same as that of the 

 surrounding wetlands. 



Operation ; The major environmental problem in SPM and tanker 

 operation will be in meeting pollutant discharge standards on waste 

 disposal and oil discharge. Constant supervision and contact will have 

 to be maintained between the single point mooring buoy and the oil 

 tanker to ensure proper and safe transfer. 



The possibility of tanker damage and oil spill are significantly 

 reduced if single point moorings can be situated where navigational 

 hazards (such as rock outcrops) are absent. Most oil spilled into water 

 initially floats at the water surface. Wind and water forces effectively 

 distribute spilled petroleum hydrocarbons into all components of the 

 marine and coastal environment, including the water column, sediments, 

 atmosphere, and the organisms present in the marine and coastal eco- 

 systems. 



Wildlife that comes in contact with an oil spill can be harmed 

 or die from ingestion of petroleum, or can lose the insulating 

 capacity of their feathers or fur. Generally, fish are ableto 

 avoid the effects of an oil spill because they swim beneath it, 

 but aquatic birds present other problems. Some diving birds 

 that fully submerge are mostly unable to walk on land and are vir- 

 tually restricted to the aquatic medium. Oil spills have drastic 

 implications to oceanic birds which are found to the aquatic 

 medium. 



In addition to direct kills of organisms, the major adverse environ- 

 mental effects of direct oil pollution of coastal waters are: (1) 

 disruption of physiological and behavioral patterns of feeding and 

 reproductive activities of aquatic species, (2) changes in physical and 

 chemical habitat, causing exclusion of species and reduction of 

 populations; and (3) stresses on the ecosystem from decomposition of 

 refinery effluents resulting in altered productivity, metabolism, system 

 structure and species diversity. 



115 



