3.9.3 Potential Sources of Disturbance 



Potential sources of major adverse effects on fish and wildlife from 

 gas processing plants include freshwater demand, contaminated wastewater 

 and solid wastes, and site development activities. Stormwater runoff 

 and cooling system effluents also may affect fish and wildlife. 



Additional potential sources of disturbance are associated with 

 related, dependent facilities. Pipelines are particularly important 

 because a gas processing plant requires a pipeline connection directly 

 from the production platform or from a marine terminal. It may also be 

 linked by pipeline to partial processing facilities or pressurized gas 

 storage facilities. The potential effects of onshore pipelines, marine 

 terminals, and offshore pipelines are reviewed in Sections 3.1, 3.2, and 

 3.3 respectively. 



Emissions to the atmosphere and noise probably have only minor effects 

 on fish and wildlife, but these disturbances do have important effects on 

 people and, therefore, may be critical in siting, design, construction, 

 and operation of gas processing plants. 



Emissions from a gas processing plant may come from processing units, 

 evaporation, flaring, and equipment such as boilers and compressors. 

 Effects from the emissions vary, depending on the composition of the gas 

 stream, the types of processing units, the pollution control equipment, 

 and the regional ambient air conditions. Emissions may include hydrogen 

 sulfide, sulfur oxides, hydrocarbons, particulates, carbon monoxide, and 

 nitrogen oxides. 



Major sources of noise from gas plants, which operate 24 hours a 

 day, include compressors, boilers, scrubbers, and flare stacks. Gas 

 plants are required by Federal pollution laws to use the best available 

 technology for suppressing noise. Where gas is stored underground in 

 salt domes, the discharge of brine solution to create storage caverns 

 may also be a pollutant. 



Subproject: Site Preparation (SP-5) 



Disturbing Activity: Clearing, grading 



Site preparation and development for a new gas processing plant 

 usually involves a relatively small amount of land. Around 20 acres may 

 be cleared with any additional land left to act as a buffer zone and to 

 allow for future expansion. Since the major waterfront need is for a 

 pipeline landfall, gas processing plants can be built inland if coastal 

 siting poses a threat of damage to wetlands or other environmental 

 problems. If an inland site is selected, land clearing and grading for 

 the processing units, operations buildings, and storage tanks should 

 have minimum potential for creating disturbances that would affect coastal 



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