Table II. Mat-erials Used in the Formulation of Insulating Materials 



Test Specimen 



Polyethylene 

 (standard polyethylene 

 insulation) 



Polyvinyl 

 Chloride (PVC) 



GR-S (SBR) 



Silicone rubber 



Neoprene 

 (Type W) 



Plasti 



Filler 



Antioxidant 



Cumarone-indene Hard clay and Polymerized 

 resin and micro- water-ground trimethyl 

 crystalline wax whiting dihydroquinoline 



Light process 4, 4 thiobis 



oil and Hard clay (6-tert-butyl 



petroleum m-creosol) 



Materials containing anti fouling paints or other toxic substances were excluded 

 from exposure aboard the STU. The current velocity at a depth of 2,340 feet was not 

 great enough (approximately 0.3 knot) to carry away any toxic substance which might 

 alter the natural biological fauna found in the immediate vicinity of the STU. 



RESULTS 



Marine Growth on STU Complex 



The upper buoy of the vertical riser line was submerged approximately 240 feet 

 below the surface of the water, the lower buoy approximately 940 feet below the 

 surface (Figure 2). A fairly dense attachment of hydroid growth over the upper half 

 section of each of the two aluminum buoys was observed when they were recovered 

 (Figure B-1 in Appendix B). A 2-inch-long pink-colored coelenterate (possibly a 

 sea anemone) was also securely attached to a buoy (Figure B-2). 



