vents. Natural gas vapor is commonly used to fill the space over the liquid 

 in LNG ship tanks and storage tanks. LNG vapors may also be used as fuel 

 for vaporizing LNG, flared or compressed, and sent out through the gas 

 transmission lines. An accident that released LNG to the atmosphere could 

 result in catastrophic explosion and fire (see Section 4.19.6). 



Subproject: Site Preparation (SP-5) 



Disturbing Activity: Clearing, grading 



A new LNG plant usually involves a relatively small amount of land for 

 equipment and structures and a large amount for a buffer zone and for future 

 expansion. Though a direct waterfront location is considered advantageous, 

 only the marine terminal and the pipeline to the plant are waterfront- 

 dependent. If an LNG plant site is set well back, land clearing and grad- 

 ing activities may have minimum potential for creating disturbances that 

 affect fish and wildlife, provided that vital areas such as wetlands and 

 endangered species habitats are avoided, watercourses are protected, and 

 erosion control and other precautions are taken. If a plant is located 

 on the waterfront, full scale site preparation and development controls 

 and precautions are required. 



Subproject: Site Development (SP-6) 



Disturbing Activity: Line constructing, installing 



The site development plan for the plant work areas must provide for 

 wastewater disposal systems and underground stormwater collection systems 

 because of the potential for leaks of toxic substances. In addition, 

 utilities, water supply, and other needs, such as storage tank containment 

 dikes capable of handling a complete spill must be provided for in the 

 site development plan. 



Subproject: Stormwater Systems (SP-12) 



Disturbing Activity: Stormwater conveyance 



LNG plant storage tanks, pipelines, and process areas have a 

 potential for leaks and spills that could contaminate stormwater runoff. 

 These areas require berms and other containment systems to handle the 

 maximum expected volume of stormwater runoff. Stormwater runoff collection 

 and treatment systems must also have adequate capacity to handle the 

 maximum anticipated quantities of liquid hydrocarbons and other toxic 

 contaminants . 



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