TRANSURANICS FROM NUCLEAR WEAPONS OPERATIONS 89 



top 5 cm of soil) in the immediate vicinity of those accident-simulation test sites; 

 probably there are on the order of a few curies from the same tests dispersed outside the 

 immediate vicinity but within a few miles of those locations. No such inventory yet has 

 been feasible for the sites of U. S. atmospheric tests. 



Very few accidents with U. S. plutonium weapons have placed transuranic materials 

 in the environment. The following weapons accidents are noted (U. S. Atomic Energy 

 Commission, 1974). One in 1960 involved the burning of a missile on its launcher at 

 Maguire Air Force Base, N. J. That fire completely melted plutonium in the nuclear 

 warhead but apparently did not lead to any appreciable dispersal. A second accident in 

 January 1966 resulted from the collision of a B-52 bomber with a tanker aircraft over 

 Palomares, Spain. Two nuclear weapons on board the bomber fell to the ground; the 

 impact detonated the high explosive in the weapons, and the contained plutonium was 

 dispersed nearby, mainly within an area totaling about 500 acres (200 ha). As the result 

 of extensive cleanup by the U. S. Air Force, the amount of residual plutonium that is 

 environmentally available from that accident has been estimated to be quite small. A 

 third accident (U. S. Air Force, 1970) involved the in-flight fire and crash of a B-52 

 bomber on the ice of an Arctic bay at Thule, Greenland, in January 1968. When the plane 

 impacted, there was a large explosion and intense fire. After that accident considerable 

 plutonium was found associated with the black crustation of burned jet fuel distributed 

 over about 30 acres (12 ha) of the snow-covered surface of the bay ice. More of the 

 material was found on the aircraft wreckage. Almost all this plutonium was removed 

 through cleanup operations. An estimated 25 Ci probably went to nearby soils and 

 bottom sediments; of the remainder, only a small fraction of the total plutonium in the 

 accident appears to have been dispersed via the atmosphere away from the crash location. 



During Operation Hardtack II at Johnston Island in 1962, four THOR missiles 

 being used in connection with the atmospheric nuclear tests failed to perform properly.* 

 Three of these missiles had to be destroyed in flight; transuranic materials from the 

 attached nuclear explosives were scattered over nearby ocean areas. A fourth THOR 

 caught fire on the launch pad on July 25, 1962, and high explosive, associated with the 

 nuclear explosive, was detonated as a protective measure. Plutonium metal and plutonium 

 oxide were scattered, as a result. There was extensive decontamination of the launch pad 

 following this specific incident; the more accessible plutonium was removed, and some 

 less-accessible material was painted over or paved over. 



From the record of these accidents, it appears that from 10 to 100 Ci of plutonium 

 may remain available in the environment from that type happening involving U. S. 

 nuclear weapons. 



Finally, transuranic materials have been released in the course of operations at the 

 laboratories and plants where nuclear weapons are designed and built. An amount 

 estimated at between 10 and 100 Ci of plutonium was released to the soil through leakage 

 from stored waste at the Rocky Flats Plant over a period of several years. About 300 Ci 

 of ^^^Pu was released at Mound Laboratory in 1969 owing to a break in a waste transfer 

 line (U. S. Atomic Energy Commission, 1975); this material, however, was not weapons 

 related. The total from all such releases at all weapons laboratories and facilities probably 



*This information is based on personal communications with Layton O'Neill, Nevada Operations 

 Office. Although the individual incidents were made public through press releases in 1962, no 

 comprehensive account has been located in published literature. 



