Patent Number: 
Section: claims

1. A module for storing high level radioactive waste, the module comprising:an outer shell having a hermetically closed bottom end;an inner shell forming a cavity configured for storing a hermetically-sealed canister containing high-level nuclear waste, the inner shell positioned inside the outer shell so as to form a space between the inner shell and the outer shell;at least one divider extending from a top of the inner shell to a bottom of the inner shell, the at least one divider creating a plurality of inlet passageways through the space, each inlet passageway connecting to a bottom portion of the cavity;a plurality of cylindrical inlet ducts arranged around a peripheral flange affixed to the outer shell, each inlet duct penetrating the flange and fluidly connecting at least one of the inlet passageways to ambient atmosphere, each inlet duct comprising an inlet duct cover affixed over a surrounding cylindrical inlet wall extending upwards from the peripheral flange, the inlet wall being peripherally perforated with a plurality of perforations; anda removable lid positioned atop the inner shell, the lid having at least one outlet passageway connecting the cavity and the ambient atmosphere, wherein the lid and a top of the inner shell are respectively configured to form a hermetic seal at a top of the cavity. 2. The module of claim 1 further comprising a blanket of insulating material connected to and surrounding the inner shell. 3. The module of claim 1 wherein the inlet wall is peripherally perforated to have a minimum of 60% open area. 4. The module of claim 1, wherein the cavity has a horizontal cross-section that accommodates no more than one canister. 5. The module of claim 1 further comprising:a bottom plenum between a bottom of the canister and a floor of the cavity;a top plenum between a bottom of the lid and a top of the canister; anda clearance existing between an outer side wall of the canister and the inner shell that connects the bottom plenum to the top plenum. 6. The module of claim 1 wherein the lid comprises:an upper shield; anda lower shield, wherein the outlet passageway connects with the cavity between the upper shield and the lower shield. 7. The module of claim 6 wherein the upper shield and the top of the inner shell are respectively configured to form the hermetic seal at the top of the cavity. 8. The module of claim 6 wherein the lower shield extends into the cavity to below the top of the cavity. 9. The module of claim 6 wherein a top of the upper shield extends to or above the inlet ducts. 10. The module of claim 1 wherein the lid has a cross-sectional profile that is larger than a cross-sectional profile of the top of the cavity. 11. The module of claim 1 wherein the lid further comprises an outlet duct connecting the at least one outlet passageway and the ambient atmosphere, the outlet duct comprising an outlet duct cover affixed over a surrounding outlet wall, the outlet wall being peripherally perforated. 12. The module of claim 11, wherein the outlet duct extends above the plurality of inlet ducts. 13. The module of claim 11, wherein the outlet wall is peripherally perforated to have a minimum of 60% open area. 14. The module of claim 1 wherein each of the inlet ducts maintains an intake air pressure substantially the same as each of the other inlet ducts. 15. A module for storing high level radioactive waste, the module comprising:an outer shell having a hermetically closed bottom end;an inner shell forming a cavity configured for storing a hermetically sealed canister containing high-level radioactive waste, the inner shell positioned inside the outer shell so as to form an annular space between the inner shell and the outer shell;at least one longitudinally-extending vertical divider extending from a top of the inner shell to a bottom of the inner shell within the annular space, the at least one divider creating a plurality of inlet passageways through the annular space, each inlet passageway fluidly connecting to a bottom portion of the cavity;a plurality of cylindrical inlet ducts arranged around a perimeter of the outer shell, each inlet duct fluidly connecting at least one of the inlet passageways to ambient atmosphere and each comprising an inlet duct cover affixed over a surrounding cylindrical inlet wall having a vertical orientation, the inlet wall being peripherally perforated with a plurality of perforations; anda removable lid positioned atop the inner shell, the lid having at least one outlet passageway connecting the cavity and the ambient atmosphere, wherein the lid and a top of the inner shell are respectively configured to form a hermetic seal at a top of the cavity;wherein each vertical divider includes a horizontal extension portion extending from the annular space through the inner shell into the cavity, the extension portion configured as a guide rib configured for engaging the canister disposed within the cavity. 16. The system of claim 15 wherein each horizontal extension of the vertical dividers further extends through a support leg extending downwards from a bottom of the inner shell. 17. A system for storing high level radioactive waste, the system comprising:a plurality of modules, each module comprising:an outer shell having a hermetically closed bottom end;an inner shell forming a cavity configured for holding a canister containing radioactive waste, the inner shell positioned inside the outer shell so as to form a space between the inner shell and the outer shell;at least one a plurality of dividers extending from a top of the inner shell to a bottom of the inner shell within the space, the at least one dividers creating a plurality of inlet passageways through the space, each inlet passageway connecting to a bottom portion of the cavity;a plurality of cylindrical inlet ducts arranged around a perimeter of the outer shell, each inlet duct connecting at least one a pair of the inlet passageways to ambient atmosphere and each comprising an inlet duct cover affixed over a surrounding cylindrical inlet wall, the inlet wall being peripherally perforated with a plurality of perforations; anda removable lid positioned atop the inner shell, the lid having at least one outlet passageway connecting the cavity and the ambient atmosphere, wherein the lid and a top of the inner shell are respectively configured to form a hermetic seal at a top of the cavity;wherein one of the plurality of dividers is associated with one of the plurality of inlet ducts forming a pair of the inlet passageways associated with each inlet duct, each pair of inlet passageways being fluidly isolated inside the module from every other pair of inlet passageways by the dividers. 18. The system of claim 17 wherein the inlet wall is peripherally perforated to have a minimum of 60% open area. 19. The system of claim 17 further comprising:a bottom plenum between a bottom of the canister and a floor of the cavity;a top plenum between a bottom of the lid and a top of the canister; anda clearance existing between an outer side wall of the canister and the inner shell that connects the bottom plenum to the top plenum. 20. The system of claim 17 wherein the lid comprises:an upper shield; anda lower shield, wherein the outlet passageway connects with the cavity between the upper shield and the lower shield.