few years after initial construction. Such was the case at Aberdeen 

 Harbor, Scotland []3]. Service bases and repair yards often are located 

 in developed harbors which are typified by the accumulation of contami- 

 nated bottom sediments. Because heavy metals, hydrocarbons and other 

 toxic compounds may be prevalent in the sediments, dredging existing har- 

 bors to improve navigation for OCS craft may require special techniques to 

 reduce the resuspension of pollutants, as well as elaborate precautions 

 in spoil containment and disposal. 



Subproject: Bulkheads (SP-3) 



Disturbing Activity: Bulkhead design 



Where no existing harbor space is available for temporary and 

 permanent service bases, new bulkheaded dock frontage for boat loading 

 and unloading may be required. To service each drilling riq, two or 

 three workboats and one crewboat may be needed, and for each drilling 

 platform, four workboats and one crewboat may be required. During the 

 long production period, one workboat usually will service two platforns. 

 No crewboats are needed because the smaller crew can be transported by 

 helicopter and workboats. For each offshore rig (temporary base) or 

 offshore platform (permanent base) serviced an estimated 200 feet of 

 waterfront is required [12]. 



Subproject: Site Preparation (SP-5) 



Disturbing Activity: Site clearing and grading (design and 

 construction) 



Activities to develop a site for a service base repair yard complex 

 vary considerably in their potential to affect fish and wildlife. The use 

 of existing harbors or other marine industrial areas may require few or 

 no site alterations. At new waterfront sites, complete clearing, grading, 

 and paving of the work, storage, and parking areas usually occurs. 

 Vegetated buffer areas are created along the perimeter of the work areas 

 to screen visual and noise disturbances and to filter runoff. 



Subproject: Site Development (SP-6) 



Disturbing Activity: Line construction, fill removal and deposition 



The working and storage areas would be leveled to maximum slopes of 

 three percent. The majority of the area would be graded and much of it 

 blacktopped. Plans for stormwater collection and treatment system, 

 utility lines and other underground facilities must be included in the 

 site development plan. 



Shoreline alteration may be proposed for a new site, including 

 filling of low areas, general filling to raise the land above flood 



38 



