so that tensile strength tests can be conducted on the recovered ropes. 

 Six inch long electrical cables covered with different insulating 

 materials (butyl rubber, neoprene rubber, natural rubber, PVC, poly- 

 ethylene, and TFE) were also tested by securing these to a phenolic 

 laminated plastic plate (Figure 2). For sign of any deterioration, 

 only visual examinations were conducted under a sterescopic microscope 

 on the recovered cable specimens. A Douglas fir panel was also 

 attached to the rack to determine if marine wood boring animals are 

 present at the sediment-seawater interface. 



Two titanium test racks (one rack to be exposed for one year 

 and the second rack for a period of two years) with materials were 

 prepared and placed in the black bottom sediment present in Port 

 Hueneme Harbor by scuba divers (Figure 3). A shovel was used by the 

 divers to bury the racks in the sediment because it contained a 

 mixture of large and small rocks and debris, making it difficult to 

 shove the racks deeply into the mud. A third rack with replicate 

 test specimens was exposed near the surface of the water from an 

 NCEL corrosion testing dock located inside the Port Hueneme Harbor. 

 The rack was suspended with a synthetic rope about three feet below 

 mean low tide from the dock. Plans are to expose this rack near the 

 surface for a period of two years so that the effects of fouling, 

 biodeterioration, and other changes which may occur to the test panels 

 can be compared to those replicate panels exposed in the bottom sedi- 

 ments. 



RESULTS AND DISCUSSION 



Bottom Rack 



The titanium rack with materials which has been exposed in the 

 bottom sediment for a period of one year was recovered by divers 

 during the month of September 1972 (Figure 4). The depth into which 

 the materials were buried in the sediment can be determined by the 

 end plate of the titanium rack (Figure 5). There was light fouling 

 growth attached to the recovered materials. The sessile organisms 

 found attached to the materials were composed mostly of encrusting 

 bryozoa (several species), calcareous tubeworms, and rock oysters. 

 These fouling organisms are not adversely affected by living in a 

 seawater environment containing hydrogen sulfide and low dissolved 

 oxygen concentration. After the plastic panels (6 x 12 inch) were 

 cleaned of marine growth, hardness and moisture absorption tests were 

 conducted. The results of these tests are presented in Table 1. 

 The hardness test was conducted over two different sections of the 

 surface of the plastic panels - the section which was buried in the 

 mud and the section which was exposed to seawater above the mudline. 

 The two sections would be distinguished by the discoloration present 

 in the plastic panel. For example, the section of a PVC panel (grey) 



