A test program conducted to develop high integrity piping and seal components for Plutonium Recycle Test Reactor installation. Methods of preventing leakage of costly D2O coolant and maintaining operational safety were investigated.

Designing a dissolver safe for up to 5 per cent U.235 enriched NPF's and having a one a ton per day capacity is a fundamental problem of Hanford NPF Program. Two basic design concepts have so far evolved, both of which employ a recirculating system in which the fuel elements are placed in the critically safe geometry separated from the bulk of the solution in another vessel. In one concept the fuel elements are charged to a set of geometrically safe cylinders or tubes and solution is circulated through them/ In the other concept the fuel elements are placed on a flat tray while solution is sprayed over them. In the latter system, nuclear safety is obtained by avoiding submerged dissolution and the resulting neutron moderation by the solution.