433 



Slide No. 9. — Shows the first of the few drums found in the site. This is an intact 

 55-gallon drum showing characteristic blistering corrosion at the chimes and weld 

 points. The surrounding terrain is irregular with marl talus blocks adjacent to the 

 drum. Corrosion products can be seen in the foraminiferal sand "downcurrent" 

 (nearest the viewer) of the drum. The ubiquitous rat-tail fish (Coryphaenoides arma- 

 tus) is seen swimming near the drum. The drum and surroundings are notable for 

 their absence of sessile (non-motile) or burrowing biological organisms. The compact- 

 ed nature of the sediment suggests an erosional surface where strong scouring 

 action has removed the surface sediment layers. 



Slide No. 10. — Shows another drum seen in the same general vicinity. It is 

 numbered "953" in yellow paint on the upper surface. The drum is considerably 

 buried by sediment but the surface paint is in good condition suggesting downslope 

 deposition with little turbidity scour. Again there is a noticeable absence of biologi- 

 cal organisms. The sediment piled up at the near-end of the drum and the straight- 

 line depressions in the background are caused by the sled track of the submersible 

 ALVIN. This drum was selected for recovery because of its good condition and 

 identification makings. Prior to recovery, a series of precisely-positioned cores were 

 taken at two meter intervals up to twelve meters from the drum. These cores were 

 analyzed for the man-made radioisotopes plutonium-238, plutonium-239, 240, and 

 cesium-137, as well as the naturally-occurring radioisotopes such as uranium, thor- 

 ium, and radium, there was no evidence of elevated plutonium-238, plutonium-239, 

 240, or cesium-137 in any of the core samples. 



Slide No. 11. — The drum recovery was carried out in a manner similar to the 1976 

 Atlantic 2800m site recovery operation described in our 1978 testimony. The sub- 

 mersible ALVIN attached the lifting harness to the drum without incident, but 

 instead of having the support ship winch the target drum off the bottom, the 

 ALVIN lifted it directly to the surface where it was then pulled out of the water by 

 the R/V ADVANCE II. Slide No. 11 shows the deck preparations for recovery. All 

 personnel wear protective clothing and radiation exposure badges. The deck is 

 covered with rubber sheeting and the drum is immediately placed into a jet-engine 

 overpack for storage and transport. 



Slide No. 12. — Is a closeup of the long axis of the waste drum shortly after 

 recovery. The identification number is clearly visible. The drum is in excellent 

 condition considering its immersion in more than 13,000 feet of water for over 

 sixteen years. There is no significant biofouling as compared with the drums seen 

 and recovered in the Atlantic 2800m and Pacific-Farallon Islands 900m dumpsites. 



Slide No. 13. — Is a closeup of the concrete-cap end of the waste package. The 

 concrete appears to be in good condition with no obvious evidence of spalling and 

 only minor surface dissolution. There is perforation of the metal rim of the drum 

 from corrosion where both sides of the metal drum were directly exposed to sea 

 water. The cylindrical hole in the concrete houses a metal pipe, probably contami- 

 nated with radioactivity. Subsequently this was found to be the only waste present 

 in the concrete matrix. The anal5d:ical objectives for recovering this drum were: (1) 

 to determine the metal corrosion rate in that portion of the drum exposed to free- 

 moving seawater; (2) to determine the corrosion rate in that portion of the metal 

 drum directly in contact with the sediment; and (3) to estimate the dissolution rate 

 of the concrete matrix. 



Slide No. U.—ls a view of the metal-capped end of this same drum showing some 

 minor evidence of corrosion and biofouling. The portion of the drum imbedded in 

 the sediment is seen in the upper left quadrant. We were fortunate that the 

 weather and seas were both calm during this very weather-dependent search and 

 recovery operation. Shortly after recovery the drum was sealed in a jet-engine 

 container overpack and purged with argon, an inert gas, to prevent further deterio- 

 ration. 



Slide No. 15. — The drum was off loaded at Port Jefferson, New York and taken to 

 Brookhaven National Laboratory (BNL) for analysis. Although the analysis is not 

 yet complete, we do have the results of a similar set of analyses performed by BNL 

 on the drum we recovered from the Atlantic 2800m site in 1976. That drum had 

 been immersed for approximately fourteen years and the analyses indicate that the 

 metal would last between 25-37 years before it would no longer provide any barrier 

 to the migration of its radioactive contents. The concrete matrix is estimated to 

 provide containment for upwards of 104 years. During the approximately fourteen 

 years of immersion, none of the cobalt-60 contaminated waste was detected to have 

 been released, while the cesium-137 had been leached from the concrete matrix into 

 the sediment immediately surrounding the drum. With reference to the estimated 

 longevity of the metal, the metal drum is not considered a primary barrier to the 

 waste and was used simply as a convenient form of handling and transport of the 

 waste for disposal. 



