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3800M DUMPSITE CHARACTERISTICS 



The biological sampling program conducted in the 3800m dumpsite area focussed 

 on the infauna (living in the sediment), epifauna (primarily megafaunal inverte- 

 brates living on the sediment), and fish. 



The infauna populations are scanty and are dominated by small nematodes, 

 crustaceans, and polychaete worms. The infaunal populations at both the Atlantic 

 2800m and 3800m dumpsites are both fewer in numbers and species per unit area 

 than either of the shallower Pacific-Farallon Islands dumpsites investigated. 



The predominant epifauna are brittle starfish (ophiuroids) and hermit crabs (pa- 

 gurids). Although the number of deepsea samples taken was very limited, the mega- 

 epifauna composition at the disposal site was comparable to similar depth locations 

 in the northwestern Atlantic. Coryphaenoides armatus (rat-tail) was the dominant 

 fish species present. It feeds on pelagic organisms as well as scavenges the bottom, 

 and probably represents an important link in deep-sea food chains since it has been 

 reported from abyssal depths around the world. In fact a feeding link was demon- 

 strated at this 3800m dumpsite between the rat-tail fish and a burrowing holothur- 

 ian (sea cucumber) Molpadia. 



The evidence of slump scarps, avalanche deposits, and lack of biological activity 

 indicates that this is a geologically unstable area. There is also visual evidence of 

 strong scouring from the southwesterly moving Western Boundary Undercurrent. 

 The area shows high topographic relief and is difficult to work in both on the 

 bottom and by trawling and other ship sampling methods. There is no evidence of 

 any elevated concentrations of radioactivity in the biota, sediments or the water, 

 with the possible exception of americium-241 in two specimens of the rat-tail fish 

 Coryphaenoides armatus. Discussion of the americium-241 is presented in more 

 detail in the Fact Sheet submitted by Dr. Mattson with his testimony. 



The future use of this site would appear undesirable based on its geologic instabil- 

 ity and the difficulty in monitoring the area. However, lack of extensive biologcial 

 populations, and the presence of strong dispersal forces would seem to suggest lower 

 potential for physical and biological accumulation of any of the radioactive waste 

 contents, thus perhaps reducing the potential impact of the dumping operations. 

 Important questions remain unanswered regarding this site — questions such as the 

 velocity and direction of the currents flowing in and around the dumpsite area, and 

 the seemingly anomalous values of americium found in two fish specimens. Further 

 sampling to answer these questions is warranted. 



2800M DUMPSITE SURVEY ACTIVITIES 



The last two ALVIN submersible dives in our 1978 Atlantic survey program were 

 conducted at the 2800m dumpsite. At the request of, and in cooperation with the 

 U.S. Navy we provided submersible time during our survey activities to: (1) Conduct 

 a brief but unsuccessful attempt to locate the SEA WOLF reactor vessel at this site. 

 (2) Assist in the deployment of corrosion test panels to study the corrosion rates 

 over time of various alloys at the depth approximating the disposal depth of the 

 N/S SEA WOLF reactor vessel. This is a long-term study. 



Slide No. 16. — Shows the corrosion test panels (foreground) in the ALVIN sam- 

 pling basket, ready for deployment on the ocean floor. 



By way of comparison with the 3800m site I have a few slides showing types of 

 wastes, in addition to radioactive waste, deposited in the 2800m dumpsite. 



Slide No. 1 7. — Shows WWII military waste of undefined content, but clearly dated 

 from that time period. 



Slide No. 18. — Is typical of the hundreds of boxes of ammunition we observed 

 while traversing the area in the ALVIN submersible. The presence of other types of 

 waste in this 2800m dumpsite complicates the identification of radioactive waste 

 drums by sonar location since ordnance and other packaged waste materials give a 

 similar sonar return signal. In addition, operating in an explosives or ammunition 

 dumping area poses a greater risk from accidental contact with the wastes them- 

 selves while exploring the bottom. Routine trawling for biologicial samples from a 

 surface ship should be done outside the immediate dumpsite area to avoid acciden- 

 tal recovery of these wastes. 



While the 3800m dumpsite appears relatively barren of biological organisms, the 

 2800m site appears more biologically active. The following six slides are illustrative 

 of some of the more common fish and invertebrates present at the 2800m dumpsite. 

 While the fish are of considerable oceanographic interest, they also compound the 

 difficulty of describing potential biological transport mechanisms for radioactivity 

 from a dumpsite. Each of the fish shown may represent part of a separate food- 

 chain or components of the same food chain. 



