A PLA is a multi-employer, multi-union, pre-hire collective bargaining agreement that PLA proponents market to public and private construction owners as a tool to systemize labor relations between multiple construction trade unions and contractors on a specific construction site.
The alpha particle given off during the radioactive decay of americium-241 is absorbed by beryllium-9, producing carbon-12 and a neutron. Such devices can be used for the nondestructive testing of machinery and equipment and for other industrial applications.
In fact, only 8 of the nuclear waste elements have isotopes which are of radioactive concern after 50 years.Of those, only 3 of the 15 Rare Earths in nuclear waste are detectably radioactive after 50 years (Promethium, Gadolinium, and Terbium).