34 TRANSURANIC ELEMENTS IN THE ENVIRONMENT 



the atmosphere. Since 1963 major underground testing, which included several hundred 

 underground nuclear devices, has been conducted but has in only a few cases released 

 radioactivity to the atmosphere. 



Most of the studies of transuranium elements from nuclear weapons testing have been 

 concerned with the measurement of 239,240pjj isotopes. However, the complete decay of 

 the accompanying short-lived ^'^^Pu (15 yr) results in the formation of a quantity of 

 ^^^Am which approaches that of ^■^^'^'^^Pu. A major injection of ^^^Pu into the 

 atmosphere occurred in April 1964 when a navigational satellite failed to achieve a stable 

 orbit and disintegrated on reentry into the atmosphere. The 17 kCi of ^^^Pu that was 

 added to the atmosphere was relatively small compared with the 360 kCi of 239,240p^ 

 that has been added by nuclear weapons testing. However, it greatly increased the 

 worldwide ^^^Pu deposition, and its point-source injection has been useful in developing 

 models describing global atmospheric mixing. 



Other incidents have added to the environmental distribution of transuranic elements 

 but not on a worldwide scale. An aerial refueling explosion involving a B-52 bomber 

 carrying four plutonium-bearing nuclear weapons and a KC-135 tanker occurred on 

 Jan. 16, 1966, 28,000 ft above the Mediterranean coastline near the Spanish village of 

 Palomares, Spain. The high-explosive component part of two weapons exploded on 

 impact, releasing the weapons plutonium inventory over the hillside outside the village. 

 On Jan. 21, 1968, a B-52 with four plutonium-bearing nuclear weapons on board 

 attempted an emergency landing at Thule Air Force Base. At 9000 ft over the base, the 

 crew bailed out, and the abandoned plane crashed on the ice of North Star Bay. The 

 high-explosive components of all weapons detonated, and the plutonium inventory was 



scattered over the ice. 



The operation of nuclear reactors also results in the production of transuranium 



elements, and the potential exists for release of some of these to the atmosphere during 

 reactor operation and subsequent fuel processing. The modern nuclear power plants, 

 which are designed for the generation of electric energy, use very long fuel exposure 

 periods and may in the future recycle the fuel to burn the resulting ^^^Pu. This results in 

 successive neutron capture of the transuranium elements and production of very 

 substantial quantities of higher mass elements. It has been estimated that approximately 

 2 X 10^ Ci of transuranium elements may be produced as radioactive waste through the 

 year 2000. Whereas 2 3 9,2 4 0pjj ^^^ ^'^^ Am are the main transuranium alpha activities 

 from nuclear weapons testing, ^^^Pu, ^'^^Am, and the curium isotopes will be the 

 principal alpha activities from nuclear reactor operations. Accidental releases of 

 transuranium elements to the atmosphere have occurred both from nuclear plant 

 operation and from the transport of nuclear weapons. The total amounts released to the 

 atmosphere by these processes have been relatively minor; however, such accidents may 

 have rather significant local effects. 



Distribution of Transuranium Elements from Nuclear Explosions 



The amounts of transuranium elements from nuclear testing distributed over the 

 world surfaces have been estimated on the basis of the nuclear tests of all nations (Hardy, 

 1964; United Kingdom Atomic Energy Authority, 1972; 1973; 1974; 1975; Nakahara 

 etal., 1975). Tables 1 to 5* are summaries of the individual tests performed by each 



*Publication of this book does not constitute a DOE endorsement of the accuracy or completeness 



of the list of alleged tests contained in these tables. 



(Text continues on page 59.) 



