Areas below this depth should have preprogrammed reserve buoyancy to 

 compensate for the anticipated weight increases. 



Active antifouling systems recommended for the upper 600 ft are: 



1. Main housing - mechanical cleaning as needed, plus additional 

 reserve buoyancy to minimize cleaning frequency. 



2. Replaceable modules (including warm and cold water outlets). 



a. Assuming refurbishment of antifouling coatings on a 

 2-yr basis: 



(1) High-quality, tested copper oxide paint (only in the 

 absence of aluminum heat exchangers) . 



(2) High-quality, tested copper oxide - organotin paint 

 (only in the absence of aluminum heat exchangers) . 



(3) High-quality, tested organotin paint (for any heat 

 exchanger) . 



b. Assuming refurbishment of antifouling coatings on a 5-yr 

 basis - organotin sheeting. 



3. Warm water intakes and screens - mechanical cleaning. 



4. Pumps. 



a. No antifouling control where velocities exceed 20 knots. 



b. Organotin sheeting on other exposed areas. Types of 

 mechanical cleaning systems have not been specified since design and 

 geometry of a finished OTEC plant have not been decided. 



RECOMMENDATIONS 

 The following recommendations are offered; 



1. Research directed toward design and construction of large 

 cathodic protection systems should be initiated. 



2. Development of a reasonable cost, implantable corrosion probe and 

 monitoring system should be undertaken. 



3. A list of acceptable anticorrosion paint suppliers should be 

 assembled. Testing selected products will require several years and 

 should commence in the near future. 



4. Additional data on rates of open ocean fouling should be 

 assembled for proposed OTEC sites. 



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