ABSTRACT
A l l of these elements are present in the plutonium production, thus reducing plutonium quality. Concentrations of such elements as boron, beryllium, lithium and fluorine were kept within a range of 10" 2-10~ 5%. The a half-life of 2 4 0 Pu is 6.6 thousand years ( 2 3 9Pu - 24.4 thousand years); thus it increases the lightmetal neutron background by a factor of 4 . Therefore, the laboratory monitoring of all process flows during the weapons plutonium production at Plant V was extremely important.
