A containment enclosure for shielding an outer cask containing an inner canister loaded with nuclear waste such as spent fuel rods. The enclosure includes a lower base portion at least partially embedded in a concrete pad and an upper radiation shielding portion defined by a shield jacket coupled to and supported by the lower base portion at a circumferential joint. Cavities of the base and shielding portions collectively define a contiguous containment space for the cask. A portion of the cask resides in each of the base and shielding portions which completely enclose and shield the cask to minimize radiation dosage of personnel in the environment surrounding the cask. The cask is cooled by a natural convectively-driven ambient cooling air ventilation system including air inlets at the circumferential joint of the enclosure. The concrete pad may be part of a spent nuclear fuel storage installation comprising plural cask containment enclosures.

A nuclear component handling arrangement is disclosed including a storage overpack including an inner envelope, an inner canister including an outer envelope, and a vent and duct system. The inner canister is positionable within the storage overpack. The vent and duct system includes an inlet vent, an outlet vent, and a passageway defined between the inner envelope of the storage overpack and the outer envelope of the inner canister. The passageway extends between the inlet vent and the outlet vent. The inlet vent includes an inlet entrance, an inlet exit, and a curved transition surface extending between the inlet entrance and the inlet exit.

A nuclear component handling arrangement is disclosed including a storage overpack including an inner envelope, an inner canister including an outer envelope, and a vent and duct system. The inner canister is positionable within the storage overpack. The vent and duct system includes an inlet vent, an outlet vent, and a passageway defined between the inner envelope of the storage overpack and the outer envelope of the inner canister. The passageway extends between the inlet vent and the outlet vent. The inlet vent includes an inlet entrance, an inlet exit, and a curved transition surface extending between the inlet entrance and the inlet exit.

A method of improving residual stress in a canister in which fuel assemblies are loaded includes, when the canister having a cylindrical canister shell and a canister lid welded to the upper opening of the canister shell is disposed in a cylindrical cask body, filling the space above and around an upper end portion of the canister in the cask body with fill water. Then, compressive stress is applied to a predetermined region of the upper end portion of the canister in the fill water. This makes it possible to readily apply compressive stress to the canister while shielding radioactive rays by the fill water.

A method of improving residual stress in a canister in which fuel assemblies are loaded includes, when the canister having a cylindrical canister shell and a canister lid welded to the upper opening of the canister shell is disposed in a cylindrical cask body, filling the space above and around an upper end portion of the canister in the cask body with fill water. Then, compressive stress is applied to a predetermined region of the upper end portion of the canister in the fill water. This makes it possible to readily apply compressive stress to the canister while shielding radioactive rays by the fill water.

The present invention provides a dry interim storage container for spent nuclear fuel, precisely a dry interim storage container that can be filled with spent nuclear fuel wherein the storage container space is also filled with metal particles. The dry storage container for spent nuclear fuel of the present invention is filled with particles in its empty space for the spent nuclear fuel, which is advantageous in cooling efficiency and maintenance cost, compared with the conventional storage method using gas.

The present invention provides a dry interim storage container for spent nuclear fuel, precisely a dry interim storage container that can be filled with spent nuclear fuel wherein the storage container space is also filled with metal particles. The dry storage container for spent nuclear fuel of the present invention is filled with particles in its empty space for the spent nuclear fuel, which is advantageous in cooling efficiency and maintenance cost, compared with the conventional storage method using gas.

A system for the storage of a radioactive waste product, wherein the radioactive waste product is located in a container and where one or more containers are stored in a bore hole drilled beneath a surface and having a bottom, wherein following placement of the one or more containers in the bore hole closer to the bottom, a fluid is added to the bore hole to a height above the upper most container, and wherein an upper cover is located above the upper most container and above the fluid to seal in the one or more containers and a non-permeable material is placed above the upper cover, a container storage area being formed within the bore hole beneath the upper cover.

A storage apparatus is provided for dry storage of radioactive nuclear waste. The storage apparatus comprises a sealed canister containing the radioactive nuclear waste and an outer ventilated metal storage overpack (VMSO). The VMSO has a plurality of vents to enable ambient air flow through the VMSO and around the canister to thereby dissipate heat from the canister. The VMSO has a side wall having an inner metal layer and one or more sets of alternating layers. Each set includes a neutron absorbing layer adjacent to another metal layer so that neutron absorbing and metal layers alternate throughout the side wall. The neutron absorbing layer or layers are designed to absorb neutron particles radiated from the radioactive nuclear waste and the metal layers are designed to absorb gamma particles radiated from the radioactive nuclear waste as well as radiated from the neutron absorbing layer or layers that result from reactions associated with absorption of neutron particles.

A storage apparatus is provided for dry storage of radioactive nuclear waste. The storage apparatus comprises a sealed canister containing the radioactive nuclear waste and an outer ventilated metal storage overpack (VMSO). The VMSO has a plurality of vents to enable ambient air flow through the VMSO and around the canister to thereby dissipate heat from the canister. The VMSO has a side wall having an inner metal layer and one or more sets of alternating layers. Each set includes a neutron absorbing layer adjacent to another metal layer so that neutron absorbing and metal layers alternate throughout the side wall. The neutron absorbing layer or layers are designed to absorb neutron particles radiated from the radioactive nuclear waste and the metal layers are designed to absorb gamma particles radiated from the radioactive nuclear waste as well as radiated from the neutron absorbing layer or layers that result from reactions associated with absorption of neutron particles.