Patent ID: 8625732

Claim:
A method of storing radioactive materials, the method comprising: a) positioning a system comprising a shell forming a cavity and having an open top, and at least one inlet ventilation duct extending from an inlet to an outlet at a bottom portion of the cavity in a below grade hole so that the inlet of the inlet ventilation duct is above grade and the outlet of the inlet ventilation duct into the cavity is below grade; b) introducing engineered fill into the hole to circumferentially surround the shell; c) lowering a canister containing radioactive materials through the open top of the shell into the cavity; and d) subsequent to the canister being lowered into the cavity, placing a removable lid on the shell; wherein the shell is formed of steel and the inlet ventilation duct is seal joined to the shell and a bottom plate attached to the shell to form a self-supporting unitary structure.