Relocation of Mooring. After 13 months of service to the Fleet, the 

 cathodically protected mooring was removed, examined, and relocated. This 

 move permitted testing in a different type of environment. The new location 

 had a muddy bottom quite different from the sandy, rocky bottom area where 

 the mooring was first installed. In addition to bottom differences, tidal currents 

 would be appreciably less. Before relocation, divers inspected a mooring in this 

 area and determined that potential readings could be taken on the ground legs 

 covered with mud without too much difficulty. 



At the time of relocation the mooring buoy was in excellent condition 

 both above and below water. The square area below the waterline of the buoy, 

 which had been sandblasted to bare steel at the start of the test program, had 

 a thin layer of tightly adhering rust and some fouling organisms but no pitting 

 or other sign of significant corrosion damage. There were irregular losses of 

 zinc from the two anodes located in the sea chests in the buoy, but plenty of 

 zinc remained for additional service. 



The mooring chains were also in excellent condition. The mooring 

 crew remarked that they looked as good as the day they were installed. Not 

 only was corrosion negligible, but the coating was in good condition. The 

 anodes had a loose, yellowish film but no fouling on them. They showed 

 no signs of passivation, such as was found by Peterson and Waldron''^ on 

 zinc anodes in the San Diego Bay. It was not practical to weigh the anodes, 

 but based on a visual inspection it was estimated that they would have an 

 effective service life of at least 8 years. The cables that were silver-soldered 

 to two of the ground legs had suffered localized damage at two points. 

 Apparently the cables were damaged in these areas by the heat from the 

 torch used in silver soldering and were later pulled apart during handling, 

 either in laying or picking up the mooring. Before relocating the mooring, 

 repairs were made by silver soldering the broken cables and then clamping 

 them to the chains with pipe clamps. I n a few places where the silver-soldered 

 joint between the cable and chain had been broken without damage to the 

 cable, repairs were also made by clamping the cable back into position. No 

 apparent damage to the pipe clamps used on the other two ground legs 

 could be detected. 



The first attempt at obtaining a potential profile at the new site was 

 made about 4 months after relocation. At that time Legs 3 and 4 were under 

 about 1 foot of mud, and Legs 1 and 2 were under about 2 to 3 feet of mud. 

 A rather strong wind and the erratic operation of one of the engines of the 

 diving boat further complicated the measurement of potentials. It was diffi- 

 cult to obtain precise readings, because the diver could not maintain contact 

 with the chain for a prolonged period of time. Two of the anodes on one of 

 the legs were buried in the mud and could not be located by the diver. As a 



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