阅读说明：本技术 危险材料罐 (Dangerous material tank ) 是由 R·A·穆勒 于 2019-06-04 设计创作，主要内容包括：一种在地下库中储存废核燃料的罐,包括第一端部分、第二端部分、以及中间部分,该中间部分可附接到第一端部分和第二端部分,以限定壳体的内容积,该内容积的尺寸设定成封围至少一个废核燃料组件。第一端部分和第二端部分包括屏蔽物。(A canister for storing spent nuclear fuel in an underground reservoir includes a first end portion, a second end portion, and an intermediate portion attachable to the first and second end portions to define an interior volume of a housing sized to enclose at least one spent nuclear fuel assembly. The first end portion and the second end portion include a shield.)

1. A tank for storing spent nuclear fuel in an underground reservoir, the tank comprising:

a first end portion;

a second end portion; and

a middle portion comprising a material configured to allow gamma rays to transmit therethrough, the middle portion attachable to the first end portion and the second end portion to define an inner volume of a housing sized to enclose at least one spent nuclear fuel assembly,

wherein the first end portion and the second end portion include a shield including a barrier to transmission of gamma rays therethrough.

2. The canister of claim 1, wherein the material comprises a barrier to the transmission therethrough of radioactive liquids, radioactive solids and radioactive gases.

3. The canister of claim 2, wherein the radioactive gas comprises tritium gas.

4. A canister as claimed in any one of the foregoing claims, characterized in that the intermediate portion comprises a circular cross-section.

5. A canister as claimed in any one of the foregoing claims, characterized in that the second end part comprises a bottom member of the canister.

6. The canister of claim 5, wherein the bottom member is mechanically attached to the intermediate portion.

7. A canister as claimed in any one of the foregoing claims, characterized in that the shield comprises a barrier for the transmission therethrough of radioactive liquids and radioactive gases.

8. The canister of any one of the preceding claims, wherein the inner volume comprises a height dimension of between about 12 feet and about 15 feet and a cross-sectional diameter of between 7 inches and 13 inches.

9. The canister of claim 8, wherein the inner volume is sized to enclose a single spent nuclear fuel assembly.

10. The canister of any of claims 1-7, wherein the internal volume comprises a height dimension of between about 24 feet and about 30 feet and a cross-sectional diameter of between 7 inches and 13 inches in diameter.

11. The canister of claim 10, wherein the inner volume is sized to enclose two or more spent nuclear fuel assemblies linearly arranged in the inner volume.

12. The canister of any one of the preceding claims, wherein the material comprises at least one of stainless steel, carbon steel, titanium or nichrome.

13. A canister as claimed in any one of the preceding claims, further comprising one or more rollers or bearings mounted to the intermediate portion.

14. The canister of any one of the preceding claims, further comprising a non-conductive material attached to the intermediate portion.

15. The canister of claim 14, wherein the non-conductive material comprises a plurality of quartz members attached to an outer surface of the intermediate portion.

16. The canister of claim 14, further comprising a non-conductive cover enclosing at least a portion of the non-conductive material.

17. A method for plugging spent nuclear fuel material, comprising:

placing at least one spent nuclear fuel assembly removed from a nuclear reactor module into an inner volume of a spent nuclear fuel tank, the spent nuclear fuel tank including a base portion and an intermediate portion attached to the base portion, the base portion and the intermediate portion defining at least a portion of the inner volume, the intermediate portion including a material configured to allow transmission of gamma rays therethrough; and

attaching a top portion of the spent nuclear fuel tank to the middle portion to enclose the at least one spent nuclear fuel assembly in the inner volume, the top portion and the base portion including a shield including a barrier to transmission of gamma rays therethrough,

wherein the spent nuclear fuel tank is configured to store at least one nuclear fuel assembly in an underground repository.

18. The method of claim 17, wherein the material comprises a barrier to the transmission therethrough of radioactive liquids, radioactive solids and radioactive gases.

19. The method of claim 18, wherein the radioactive gas comprises tritium gas.

20. The method of any of the preceding claims 17-19, wherein the intermediate portion comprises a circular cross-section.

21. A method according to any of the preceding claims 17-20, wherein a bottom member is mechanically attached to the intermediate portion.

22. The method of any of the preceding claims 17-21, wherein the shield comprises a barrier to the transmission of radioactive liquids and radioactive gases therethrough.

23. The method of any of the preceding claims 17-22, wherein the internal volume comprises a height dimension of between about 12 feet and about 15 feet and a cross-sectional diameter of between 7 inches and 13 inches.

24. The method of claim 23, wherein the internal volume is sized to enclose a single spent nuclear fuel assembly.

25. The method of any of the preceding claims 17-22, wherein the internal volume comprises a height dimension of between about 24 feet and about 30 feet and a cross-sectional diameter of between 7 inches and 13 inches.

26. The method of claim 25, wherein the internal volume is sized to enclose two or more spent nuclear fuel assemblies linearly arranged in the internal volume.

27. The method of any of the preceding claims 17-26, wherein the material comprises at least one of stainless steel, carbon steel, titanium, or nichrome.

28. The method of any one of the preceding claims 17-27, wherein the spent nuclear fuel tank further comprises one or more rollers or bearings mounted to the intermediate portion.

29. The method of any of the preceding claims 17-28, wherein the spent nuclear fuel tank further comprises a non-conductive material attached to the intermediate portion.

30. The method of claim 29, wherein the non-conductive material comprises a plurality of quartz members attached to an outer surface of the intermediate portion.

31. The method of claim 29, wherein the spent nuclear fuel tank further comprises a non-conductive cover enclosing at least a portion of the non-conductive material.

Technical Field

The present disclosure relates to a hazardous material tank, and more particularly, to a tank for spent nuclear fuel.

Background

Hazardous waste is often placed in long-term, permanent or semi-permanent stores to prevent health problems in people living near the stored waste. Storage of such hazardous waste materials is often challenging, for example, in terms of storage location identification and closure assurance. For example, the safe storage of nuclear waste (e.g., spent nuclear fuel from commercial power reactors, test reactors, or even advanced military waste) is considered one of the significant challenges of energy technology. Safe storage of long-life radioactive waste is a major obstacle to the adoption of nuclear energy in the united states and worldwide.

Disclosure of Invention

In a general embodiment, a canister for storing spent nuclear fuel in an underground reservoir includes a first end portion, a second end portion, and an intermediate portion attachable to the first and second end portions to define an interior volume of a housing sized to enclose at least one spent nuclear fuel assembly. The first end portion and the second end portion include a shield.

In some aspects that may be combined with the general implementation, the intermediate portion includes a material configured to allow transmission of gamma rays therethrough.

In another aspect that may be combined with any of the preceding aspects, the material includes a barrier to the transmission therethrough of radioactive liquids, radioactive solids, and radioactive gases.

In another aspect that may be combined with any of the preceding aspects, the radioactive gas includes tritium gas.

In another aspect that may be combined with any of the preceding aspects, the intermediate portion includes a circular cross-section.

In another aspect that may be combined with any of the preceding aspects, the second end portion includes a bottom member of the tank.

In another aspect that may be combined with any of the preceding aspects, a bottom member is mechanically attached to the intermediate portion.

In another aspect that may be combined with any of the preceding aspects, the mechanical attachment includes welding.

In another aspect that may be combined with any of the preceding aspects, the shield includes a barrier to the transmission therethrough of gamma rays, and the shield includes a barrier to the transmission therethrough of radioactive liquids and radioactive gases.

In another aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 12 feet and about 15 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In another aspect combinable with any of the preceding aspects, the internal volume is sized to enclose a single spent nuclear fuel assembly.

In another aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 24 feet and about 30 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In another aspect combinable with any of the preceding aspects, the internal volume is sized to enclose two or more spent nuclear fuel assemblies linearly arranged therein.

In another aspect that may be combined with any of the preceding aspects, the material comprises stainless steel or carbon steel.

In another aspect that may be combined with any of the preceding aspects, the material includes titanium or a nickel-chromium alloy.

Another aspect combinable with any of the preceding aspects further includes one or more rollers or bearings mounted to the intermediate portion.

Another aspect that may be combined with any of the preceding aspects, further includes a non-conductive material attached to the intermediate portion.

In another aspect that may be combined with any of the preceding aspects, the non-conductive material includes a plurality of quartz members attached to an outer surface of the intermediate portion.

In another aspect that may be combined with any of the preceding aspects, at least a portion of the plurality of quartz members includes spherical or partially spherical quartz members.

Another aspect that may be combined with any of the preceding aspects, further includes a non-conductive covering that encloses at least a portion of the non-conductive material.

In another aspect that may be combined with any of the preceding aspects, the non-conductive covering includes a fiberglass jacket.

In another general embodiment, a method for plugging spent nuclear fuel material includes: removing at least one spent nuclear fuel assembly from the nuclear reactor module; placing at least one spent nuclear fuel assembly into an inner volume of a spent nuclear fuel tank, the spent nuclear fuel tank including a base portion and an intermediate portion attached to the base portion, the base portion and the intermediate portion defining at least a portion of the inner volume; and attaching a top portion of the spent nuclear fuel tank to the middle portion to enclose the at least one spent nuclear fuel assembly in the inner volume, the top portion and the base portion including a shield. The spent nuclear fuel tank is configured to store at least one nuclear fuel assembly in an underground repository.

In some aspects that may be combined with the general embodiment, the intermediate portion includes a material configured to allow gamma rays to be transmitted therethrough.

In another aspect that may be combined with any of the preceding aspects, the material includes a barrier to the transmission therethrough of radioactive liquids, radioactive solids, and radioactive gases.

In another aspect that may be combined with any of the preceding aspects, the radioactive gas includes tritium gas.

In another aspect that may be combined with any of the preceding aspects, the intermediate portion includes a circular cross-section.

In another aspect that may be combined with any of the preceding aspects, a bottom member is mechanically attached to the intermediate portion.

In another aspect that may be combined with any of the preceding aspects, the mechanical attachment includes welding.

In another aspect that may be combined with any of the preceding aspects, the shield includes a barrier to the transmission therethrough of gamma rays, and the shield includes a barrier to the transmission therethrough of radioactive liquids and radioactive gases.

In another aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 12 feet and about 15 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In another aspect combinable with any of the preceding aspects, the internal volume is sized to enclose a single spent nuclear fuel assembly.

In another aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 24 feet and about 30 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In another aspect combinable with any of the preceding aspects, the internal volume is sized to enclose two or more spent nuclear fuel assemblies linearly arranged therein.

In another aspect that may be combined with any of the preceding aspects, the unshielded material includes stainless steel or carbon steel.

In another aspect that may be combined with any of the preceding aspects, the material includes titanium or a nickel-chromium alloy.

Another aspect combinable with any of the preceding aspects further includes one or more rollers or bearings mounted to the intermediate portion.

Another aspect that may be combined with any of the preceding aspects, further includes a non-conductive material attached to the intermediate portion.

In another aspect that may be combined with any of the preceding aspects, the non-conductive material includes a plurality of quartz members attached to an outer surface of the intermediate portion.

In another aspect that may be combined with any of the preceding aspects, at least a portion of the plurality of quartz members includes spherical or partially spherical quartz members.

Another aspect that may be combined with any of the preceding aspects, further includes a non-conductive covering enclosing at least a portion of the non-conductive material.

In another aspect that may be combined with any of the preceding aspects, the non-conductive covering includes a fiberglass jacket.

Another aspect combinable with any of the preceding aspects further includes: moving the spent nuclear fuel tank through an inlet of a bore extending into the earth's surface, the inlet at least adjacent the earth's surface; moving a spent nuclear fuel tank through a bore, the bore comprising a generally vertical portion, a transition portion, and a generally horizontal portion, the spent nuclear fuel tank sized to fit from a bore entrance through the generally vertical portion, the transition section, and the generally horizontal portion of the bore; moving the spent nuclear fuel tanks into an underground repository coupled to a substantially horizontal portion of the borehole, the underground repository being located within or below a shale layer and vertically isolated from an underground region including flowing water by the shale layer; and forming a seal in the borehole, the seal isolating the reservoir portion of the borehole from the entrance to the borehole.

In another aspect that may be combined with any of the preceding aspects, the subterranean reservoir is formed below a shale layer and is vertically isolated from a subterranean zone including flowing water by the shale layer.

In another aspect that may be combined with any of the preceding aspects, the subterranean reservoir is formed within a shale layer and is vertically isolated from a subterranean zone comprising mobilized water by at least a portion of the shale layer.

In another aspect that may be combined with any of the preceding aspects, the geological properties of the shale layer include two or more of: a permeability of less than about 0.01 millidarcys (millidarcys); a brittleness of less than about 10MPa, wherein brittleness is a ratio of a compressive stress of the shale layer to a tensile strength of the shale layer; a thickness proximate the storage area of at least about 100 feet; or about 20 to 30% by volume of the organic material or clay.

In another aspect that may be combined with any of the preceding aspects, the borehole further includes at least one casing extending from at or near the earth's surface, through the borehole, and into an underground reservoir.

Another aspect combinable with any of the preceding aspects further includes: a borehole is formed from the surface to the shale layer prior to moving the spent nuclear fuel tank through an entrance of the borehole extending into the surface.

Another aspect combinable with any of the preceding aspects further includes: a casing is installed in the borehole, extending from at or near the surface of the earth, through the borehole, and into an underground storage reservoir.

Another aspect combinable with any of the preceding aspects further includes: the casing (cement) is cemented to the borehole.

Another aspect combinable with any of the preceding aspects further includes: after the borehole is formed, hydrocarbon fluids are produced from the shale formation, through the borehole, and to the surface.

Another aspect combinable with any of the preceding aspects further includes: removing the seal from the bore; and retrieving spent nuclear fuel tanks from the underground repository to the surface.

Another aspect combinable with any of the preceding aspects further includes: monitoring at least one variable associated with the spent nuclear fuel tanks from a sensor near the underground repository; and recording the monitored variable at the surface.

In another aspect that may be combined with any of the preceding aspects, the monitored variable includes at least one of a radiation level, a temperature, a pressure, a presence of oxygen, a presence of water vapor, a presence of liquid water, an acidity, or seismic activity.

Another aspect combinable with any of the preceding aspects further includes: removing the seal from the borehole based on the monitored variable exceeding a threshold; and retrieving spent nuclear fuel tanks from the underground repository to the surface.

Another aspect combinable with any of the preceding aspects further includes: placing a cylindrical shield comprising a shielded material around an entrance to a borehole; and lowering the spent nuclear fuel tank through the cylindrical shield and into the entrance of the bore hole.

In another aspect that may be combined with any of the preceding aspects, moving the spent nuclear fuel tanks into an underground repository coupled to a substantially horizontal portion of the borehole comprises: the spent nuclear fuel tanks are moved on at least one wheel or roller.

In another general embodiment, a canister for storing spent nuclear fuel in an underground reservoir includes a first end portion, a second end portion, and an intermediate portion including a material configured to allow transmission of gamma rays therethrough, attachable to the first end portion and the second end portion to define an inner volume of a housing sized to enclose at least one spent nuclear fuel assembly. The first and second end portions include a shield including barriers to transmission of gamma rays therethrough.

In certain aspects that may be combined with general embodiments, the material includes barriers to the transport of radioactive liquids, radioactive solids, and radioactive gases therethrough.

In a certain aspect that may be combined with any of the preceding aspects, the radioactive gas comprises tritium gas.

In a certain aspect that may be combined with any of the preceding aspects, the intermediate portion includes a circular cross-section.

In a certain aspect that may be combined with any of the preceding aspects, the second end portion includes a bottom member of the tank.

In a certain aspect that may be combined with any of the preceding aspects, the bottom member is mechanically attached to the intermediate portion.

In a certain aspect that may be combined with any of the preceding aspects, wherein the shield includes a barrier to the transmission therethrough of radioactive liquid and radioactive gas.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 12 feet and about 15 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume is sized to enclose a single spent nuclear fuel assembly.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 24 feet and about 30 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume is sized to enclose two or more spent nuclear fuel assemblies linearly arranged in the internal volume.

In a certain aspect that may be combined with any of the preceding aspects, the material includes at least one of stainless steel, carbon steel, titanium, or nichrome.

Some aspects that may be combined with any of the preceding aspects further include one or more rollers or bearings mounted to the intermediate portion.

Some aspect that may be combined with any of the preceding aspects, further includes a non-conductive material attached to the intermediate portion.

In a certain aspect that may be combined with any of the preceding aspects, the non-conductive material includes a plurality of quartz members attached to an outer surface of the intermediate portion.

Some aspect that may be combined with any of the preceding aspects, further includes a non-conductive covering that encloses at least a portion of the non-conductive material.

In another general embodiment, a method for plugging spent nuclear fuel material comprises: placing at least one spent nuclear fuel assembly removed from a nuclear reactor module into an inner volume of a spent nuclear fuel tank, the spent nuclear fuel tank including a base portion and an intermediate portion attached to the base portion, the base portion and the intermediate portion defining at least a portion of the inner volume, the intermediate portion including a material configured to allow transmission of gamma rays therethrough; and attaching a top portion of the spent nuclear fuel tank to the middle portion to enclose the at least one spent nuclear fuel assembly in the inner volume, the top portion and the base portion including a shield including a barrier to transmission of gamma rays therethrough. The spent nuclear fuel tank is configured to store at least one nuclear fuel assembly in an underground repository.

In certain aspects that may be combined with general embodiments, the material includes barriers to the transport of radioactive liquids, radioactive solids, and radioactive gases therethrough.

In a certain aspect that may be combined with any of the preceding aspects, the radioactive gas comprises tritium gas.

In a certain aspect that may be combined with any of the preceding aspects, the intermediate portion includes a circular cross-section.

In a certain aspect that may be combined with any of the preceding aspects, the bottom member is mechanically attached to the intermediate portion.

In some aspects that may be combined with any of the preceding aspects, the shield includes a barrier to the transmission of radioactive liquid and radioactive gas therethrough.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 12 feet and about 15 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume is sized to enclose a single spent nuclear fuel assembly.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume includes a height dimension of between about 24 feet and about 30 feet and a cross-sectional diameter of between 7 inches and 13 inches.

In a certain aspect that may be combined with any of the preceding aspects, the internal volume is sized to enclose two or more spent nuclear fuel assemblies linearly arranged in the internal volume.

In a certain aspect that may be combined with any of the preceding aspects, the material includes at least one of stainless steel, carbon steel, titanium, or nichrome.

In a certain aspect that may be combined with any one of the preceding aspects, the spent nuclear fuel tank further comprises one or more rollers or bearings mounted to the intermediate portion.

In a certain aspect that may be combined with any of the preceding aspects, the spent nuclear fuel tank further comprises a non-conductive material attached to the intermediate portion.

In a certain aspect that may be combined with any of the preceding aspects, the non-conductive material includes a plurality of quartz members attached to an outer surface of the intermediate portion.

In a certain aspect that may be combined with any of the preceding aspects, the spent nuclear fuel tank further comprises a non-conductive cover enclosing at least a portion of the non-conductive material.

Embodiments of the hazardous-material tank according to the present disclosure may include one or more of the following features. For example, hazardous material tanks according to the present disclosure may provide faster and more cost effective tanks for long term storage in specific storage locations and permanent disposal of spent nuclear fuel. As another example, a hazardous material tank according to the present disclosure may allow one or more spent nuclear fuel assemblies to be moved from a nuclear reactor to one or more temporary storage locations (e.g., spent nuclear fuel pools, dry shielded casks), and then to the tank in the same or substantially the same configuration, thereby reducing human time and potential radiation exposure due to unpacking and repackaging (perhaps multiple times) fuel rods from the assembly. A hazardous-material tank according to the present disclosure may also be more compact and lighter in weight than conventional containers for storing hazardous materials (such as spent nuclear fuel), thereby reducing the cost of handling such tanks while improving safety. Furthermore, hazardous materials according to the present disclosure that are unshielded at the sides but shielded at the ends may provide the described advantages while also allowing for safe handling of the tanks above ground (e.g., between a nuclear reactor or spent nuclear fuel pool and a storage site). For example, a hazardous material tank storing spent nuclear fuel can be slid into a concrete (or steel or lead) container without closing the top or bottom of the container. This means that the connector (e.g. handle, latch or other) at the end of the canister remains exposed for easy connection or disconnection, for example when the canister is placed in the upper part of the bore hole.

As described, hazardous material tanks according to the present disclosure may be stored in hazardous material storage reservoirs, allowing for multiple levels of plugging of hazardous material in storage reservoirs located thousands of feet underground, separated from any nearby flowing water. A hazardous materials repository according to the present disclosure may also use proven techniques (e.g., drilling) to create or form a storage area for hazardous materials in a subterranean zone. As another example, a hazardous materials repository according to the present disclosure may provide long-term (e.g., thousands of years) storage of hazardous materials (e.g., radioactive waste) in formations, such as shale, salt, and other rock formations, having geological characteristics suitable for such storage, including low permeability, thickness, ductility, and the like. Additionally, a greater amount of hazardous material can be stored at lower cost relative to conventional storage techniques, due in part to directional drilling techniques, which can facilitate longer horizontal wellbores, typically over one mile in length. Additionally, rock formations having suitable geological properties for such storage may be found in close proximity to locations where hazardous materials may be found or generated, thereby reducing the risks associated with transporting such hazardous materials.

Embodiments of hazardous materials repositories in accordance with the present disclosure may also include one or more of the following features. The large storage volume in turn allows the storage of hazardous materials to be placed without complicated prior treatment, such as concentration or conversion to different forms or transfer to tanks. As another example, for nuclear waste material, such as from a reactor, the waste may be retained unmodified in its original pellets, or in its original fuel rods, or in its original fuel components including typically between 60 and 270 fuel rods. In another aspect, the hazardous material may be held in the original holder, but a binder (cement) or other material is injected into the holder to fill the gap between the hazardous material and the structure. For example, if hazardous materials are stored in the fuel rods, which are then further stored in the fuel component, the spaces between the rods (which are typically filled with water when inside a nuclear reactor) may be filled with a binder, bentonite or other material to provide an additional barrier from the environment. The material may be low oxygen, which may be replaced with nitrogen or an inert gas to reduce corrosion. As yet another example, the storage of safe and low cost hazardous materials is facilitated while still allowing retrieval of such materials, if the situation deems it advantageous to retrieve the stored materials.

The details of one or more embodiments of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims.

Drawings

FIG. 1A is a schematic view of an exemplary embodiment of a hazardous-material tank according to the present disclosure.

FIG. 1B is an illustration of a spent nuclear fuel assembly that may be plugged into the hazardous material tank shown in FIG. 1A, when removed from a nuclear reactor.

FIG. 1C is a diagrammatic view of a spent nuclear fuel rod that is part of the spent nuclear fuel assembly shown in FIG. 1B.

FIG. 1D is a schematic view of another exemplary embodiment of a hazardous-material tank according to the present disclosure.

Fig. 2A-2C are schematic diagrams of an exemplary embodiment of a hazardous materials repository system according to the present disclosure during a deposit or retrieval operation.

Fig. 3A-3E are schematic diagrams of an exemplary embodiment of a hazardous materials repository system according to the present disclosure during storage and monitoring operations.

FIG. 4 is a flow chart illustrating an exemplary method associated with storing hazardous materials according to the present disclosure.

FIG. 5 is a schematic diagram of a controller or control system for monitoring a hazardous materials repository system according to the present disclosure.

Detailed Description

Fig. 1A is a schematic diagram of an exemplary embodiment of a hazardous-material tank 100 according to the present disclosure. FIG. 1A shows an isometric view of a hazardous-material tank 100. In some aspects, the hazardous material tank 100 may be used in a hazardous materials repository system 200 as shown in fig. 2A-2C, or in other hazardous materials repository systems according to the present disclosure. The hazardous materials tank 100 may be used to store chemical hazardous materials, biological hazardous materials, nuclear hazardous materials, or others. For example, in the illustrated embodiment, the hazardous-material tank 100 stores spent nuclear fuel in the form of one or more spent nuclear fuel assemblies.

As shown, the hazardous material tank 100 includes a housing 102 (e.g., an anti-extrusion housing), the housing 120 having a top portion 106 and a bottom portion 104, the top portion 106 and the bottom portion 104 collectively enclosing a volume 105 for storing hazardous material. In this example, the housing 102 or middle portion 102 of the canister is shown as having a circular cross-section to accommodate the general shape of spent nuclear fuel assemblies (as shown in FIG. 1B). However, other embodiments of the can 100 may have other cross-sectional shapes, such as oval, square, or other shapes.

The top portion 106 and the bottom portion 104 may be made of or include a shield of a composition material and thickness that forms a barrier to the transmission of any hazardous material (liquid, gas, or solid) therethrough (into the tank 100 or out of the tank 100). The shield also reduces the radiation intensity to a level that allows safe handling of the tank 100 (e.g., by a human operator). In some aspects, the shield may be lead, tungsten, steel, titanium, nickel, or concrete, or an alloy or combination of these materials, with a thickness sufficient to form a sufficient barrier to the transmission of radiation such as gamma rays and X-rays (collectively "gamma rays") therethrough. The shielding on the top and bottom portions 106, 104 allows for easier handling of the canister and greater safety for persons in its vicinity. An exemplary thickness is between 2 and 4 inches for lead shielding and between 3 and 5 feet for concrete shielding.

In an exemplary embodiment of the hazardous materials tank 100, the intermediate portion 102 may be made of a material having a composition and thickness that forms a barrier to the transmission therethrough (into the tank 100 or out of the tank 100) of any hazardous materials (liquids, gases, or solids) but does not form a barrier to the transmission therethrough of gamma rays. Further, in some aspects, the unshielded material may be steel, such as carbon steel, having a thickness sufficient to form a barrier to the transmission of any hazardous materials (fluids or solids) therethrough, but not to the transmission of gamma rays therethrough. In a particular embodiment, the barrier to liquid, gas or solid leaks may be made of alloy-22 (nickel alloy) which is also used for the intermediate portion 102, and a layer of lead placed only at the ends of the can 100 to prevent gamma radiation from escaping in the direction of the long axis of the can 100.

Hazardous waste, particularly nuclear material waste, such as spent nuclear fuel, may take several forms, such as solids, liquids and gases. For example, the solid form of nuclear waste in spent nuclear fuel may be or include nuclear fuel pellets formed from, for example, sintered uranium. The gaseous form of the nuclear waste may be, for example, tritium gas (or a gas containing other radioactive isotopes), which may be vented from the solid nuclear waste, or entrained in a liquid in contact with the solid nuclear waste. The liquid form of the nuclear waste may for example be any liquid that contacts and absorbs some of the solid or gaseous nuclear waste material.

As shown in the exemplary hazardous-materials tank 100 shown in fig. 1A, the internal volume 105 may be sized (and shaped) to receive one or more spent nuclear fuel assemblies (e.g., arranged end-to-end) such as the spent nuclear fuel assembly 150 shown in fig. 1B. Turning briefly to FIG. 1B, a single nuclear fuel assembly 150 is shown. A nuclear fuel assembly 150 (also referred to as a "spent nuclear fuel assembly" 150 to indicate that it has been removed from a reactor, such as a pressurized water reactor or other type of reactor, due to an end of service life occurring during operation) includes a top portion 152 and a bottom portion 160 with a plurality (e.g., 60-300) of nuclear fuel rods 154 held between the top portion 152 and the bottom portion 160.

As shown, the nuclear fuel assembly 150 further includes a plurality of control rods 156 located between the nuclear fuel rods 154; during operation (e.g., fission) of a nuclear fuel assembly 150 in a reactor vessel of a nuclear reactor, the control rods 156 may be adjustably positioned (vertically within the assembly) to control the nuclear reaction occurring in the reactor. Such control rods 156 may be removed from the nuclear fuel assembly 150 when the assembly 150 is removed from the reactor. Accordingly, the spent nuclear fuel assembly 150 may not include the control rods 156. In particular, again, the nuclear fuel assembly 150 does not include any gamma or X-ray shielding surrounding the nuclear fuel rods 154 located in the assembly 150.

Turning briefly to FIG. 1C, an exemplary nuclear fuel rod 154 is illustrated. The nuclear fuel rod 154 includes a plurality (e.g., 300 or more) of nuclear fuel pellets 164 encased in an cladding 166 (e.g., a zirconium alloy cladding). Each of the nuclear fuel pellets 164 may be formed of, for example, sintered uranium dioxide. One or more springs 162 may be located at a top portion of the rod 154 to securely retain the fuel pellets 164 within the cladding 166. A base 168 is provided at the bottom of the fuel rod 154 to fit within the nuclear fuel assembly 150.

The height of the exemplary nuclear fuel assembly 150 (e.g., from the bottom of the bottom portion 160 to the top of the top portion 152) may be, for example, between 12 and 15 feet. Further, the width and length dimensions may be, for example, about 5.5 to 8.5 inches, respectively (e.g., each side of the generally square cross-section is between about 5.5 to 8.5 inches). Thus, in some aspects, the tank 100 may be between 12 and 15 feet in height (to store a single spent nuclear fuel assembly 150) and between 7 and 13 inches in diameter.

Returning to fig. 1A, the top portion 106 (in some aspects, the bottom portion 104) of the hazardous-material tank 100 shown may include a connecting portion. In some aspects, the connection portion may facilitate coupling of the hazardous-material canister 100 with a downhole tool (e.g., the downhole tool 228 shown in fig. 2A) to allow the hazardous-material canister 100 to be stored in a borehole and retrieved from storage in the borehole. In addition, the connecting portion may facilitate the coupling of one hazardous-material tank 100 with another hazardous-material tank 100. In some aspects, the connection portion may be a threaded connection. For example, the connection portion on one end of the can 100 may be a male threaded connection, while the connection portion on the opposite end of the can 100 may be a female threaded connection. In an alternative aspect, the connection portion may be an interlocking latch such that rotation (e.g., 360 degrees or less) may latch (or unlatch) the canister 100 with a downhole tool or other hazardous material canister 100. In alternative aspects, the connection portion may include one or more magnets (e.g., rare earth magnets, electromagnets, combinations thereof, or otherwise) that are attractively coupled to, for example, a downhole tool or another hazardous material canister 100.

In this example, one or more spent nuclear fuel assemblies 150 are positioned in the inner volume 105 prior to sealing the hazardous-material tank 100. As described above, each spent nuclear fuel rod 154 includes a plurality of spent nuclear fuel pellets 164 that are bound at the ends. For example, the spent nuclear fuel pellets 164 contain most of the radioactive isotopes (including tritium) of spent nuclear fuel removed from a nuclear reactor. The cladding of the nuclear fuel rod 154 provides an additional level of plugging.

In some aspects, the hazardous material tank 100 can be sized to enclose a single spent nuclear fuel assembly 150, which single spent nuclear fuel assembly 150 can be removed directly from the nuclear reactor and placed in the internal volume 105 (e.g., without any or substantial changes to the spent nuclear fuel assembly 150). In some aspects, the hazardous material tank 100 may be sized to enclose two or more spent nuclear fuel assemblies 150, which two or more spent nuclear fuel assemblies 105 may be directly removed from the nuclear reactor and placed vertically (e.g., end-to-end) in the internal volume 105.

Further, the hazardous-material tank 100 may generally be sized to fit within a bore, such as bore 204. Exemplary dimensions of the tank 100 may include a length L of between 12 and 15 feet, and in the case of a round tank 100, a diameter of between 7 and 13 inches. In an alternative aspect, the canister 100 may have a square cross-section sized to hold the spent nuclear fuel assemblies 150. In some examples, the hazardous-material tank 100 may be sized (e.g., length and width/diameter) for efficient stocking into and retrieval from the bore 204. For example, the length may be determined based on the radius dimension of the radiused portion 208 to ensure that the hazardous material tank 100 may move through the radiused portion 208 and into the substantially horizontal portion 210. As another example, the diameter may be determined based on the diameter of one or more casings in the borehole 204, such as the surface casing 220 and the production casing 222.

FIG. 1D is a schematic diagram of another exemplary embodiment of a hazardous-material tank 170 according to the present disclosure. FIG. 1D shows an isometric view of the hazardous-material tank 170. In some aspects, the hazardous materials tank 170 may be used in conjunction with the tank 100 or in place of the tank 100 in the hazardous materials repository system 200, or in other hazardous materials repository systems according to the present disclosure. The hazardous materials tank 170 may be used to store chemical hazardous materials, biological hazardous materials, nuclear hazardous materials, or others. For example, in the illustrated embodiment, the hazardous materials tank 170 stores spent nuclear fuel in the form of one or more spent nuclear fuel assemblies.

As shown, the hazardous material tank 170 includes a housing 172 (e.g., an anti-extrusion housing) with the housing 120 having a top portion 176 and a bottom portion 174, the top portion 176 and the bottom portion 174 collectively enclosing a volume 175 for storing hazardous material. In this example, the housing 172 or the middle portion 172 of the canister is shown as having a circular cross-section to accommodate the general shape of spent nuclear fuel assemblies (as shown in FIG. 1B). However, other embodiments of the canister 170 may have other cross-sectional shapes, such as oval, square, or other shapes.

The top and bottom portions 176, 174 may be made of or include a shield of a composition material and thickness that forms a barrier to the transmission of any hazardous material (liquid, gas, or solid) therethrough (into the tank 170 or out of the tank 170). The shield also reduces the radiation intensity to a level that allows safe handling (e.g., by a human operator) of the canister 170. In some aspects, the shield may be lead, tungsten, steel, titanium, nickel, or concrete, or an alloy or combination of such materials, with a thickness sufficient to form a sufficient barrier to the transmission of radiation, such as gamma rays, therethrough. The shielding on the top and bottom portions 176, 174 allows for easier handling of the canister and greater safety to persons in its vicinity. An exemplary thickness is between 2 and 4 inches for lead shielding and between 3 and 5 feet for concrete shielding.

In an exemplary embodiment of the hazardous materials tank 170, the middle portion 172 may be made of a material having a composition and thickness that forms a barrier to the transmission of any hazardous materials (liquid, gas, or solid) therethrough (into the tank 170 or out of the tank 170) but does not form a barrier to the transmission of gamma rays therethrough. Further, in some aspects, the unshielded material may be steel, such as carbon steel, having a thickness sufficient to form a barrier to the transmission therethrough of any hazardous materials (fluids or solids), but not to gamma and X-rays.

Hazardous waste, particularly nuclear material waste, such as spent nuclear fuel, may take several forms, such as solids, liquids and gases. For example, the solid form of nuclear waste in spent nuclear fuel may be or include nuclear fuel pellets formed from, for example, sintered uranium. The gaseous form of the nuclear waste may be, for example, tritium gas (or a gas containing other radioactive isotopes), which may be vented from the solid nuclear waste, or entrained in a liquid in contact with the solid nuclear waste. The liquid form of the nuclear waste may for example be any liquid that contacts and absorbs some of the solid or gaseous nuclear waste material.

As shown in the example hazardous-materials tank 170 shown in fig. 1D, the internal volume 175 may be sized (and shaped) to receive one or more spent nuclear fuel assemblies (e.g., arranged end-to-end) such as the spent nuclear fuel assemblies 150 shown in fig. 1B. The space in the fuel assembly may be filled with a gas (such as nitrogen), a powder (e.g. bentonite), a liquid (such as a liquid hydrocarbon), or a solid (such as a cement binder or epoxy), or a combination (such as oil and bentonite or fiberglass composed of fiberglass and epoxy).

The top portion 176 (in some aspects, the bottom portion 174) of the hazardous material tank 170 shown may include a connecting portion. In some aspects, the connection portion may facilitate coupling of the hazardous-material canister 170 with a downhole tool (e.g., the downhole tool 228 shown in fig. 2A) to allow the hazardous-material canister 170 to be stored in the borehole and retrieved from storage in the borehole. Further, the connection portion may facilitate the coupling of one hazardous-material tank 170 with another hazardous-material tank 170. In some aspects, the connection portion may be a threaded connection. For example, the connection portion on one end of the canister 170 may be a male threaded connection and the connection portion on the opposite end of the canister 170 may be a female threaded connection. In an alternative aspect, the connection portion may be an interlocking latch such that rotation (e.g., 360 degrees or less) may latch (or unlatch) the canister 170 with a downhole tool or other hazardous material canister 170. In alternative aspects, the connection portion may include one or more magnets (e.g., rare earth magnets, electromagnets, combinations thereof, or otherwise) that are attractively coupled to, for example, a downhole tool or another hazardous material canister 170.

In this example, one or more spent nuclear fuel assemblies 150 are positioned in the internal volume 175 prior to sealing the hazardous-materials tank 170. As described above, each spent nuclear fuel rod 154 includes a plurality of spent nuclear fuel pellets 164 that are bound at the ends. For example, the spent nuclear fuel pellets 164 contain most of the radioactive isotopes (including tritium) of spent nuclear fuel removed from a nuclear reactor. The cladding of the nuclear fuel rod 154 provides an additional level of plugging.

In some aspects, the hazardous material tank 170 can be sized to enclose a single spent nuclear fuel assembly 150, which single spent nuclear fuel assembly 150 can be directly removed from the nuclear reactor and placed in the internal volume 175 (e.g., without any or substantial changes to the spent nuclear fuel assembly 150). In some aspects, the hazardous material tank 170 may be sized to enclose two or more spent nuclear fuel assemblies 150, which two or more spent nuclear fuel assemblies 150 may be directly removed from the nuclear reactor and placed vertically (e.g., end-to-end) in the internal volume 175.

Further, the hazardous-material tank 170 may generally be sized to fit within a bore, such as bore 204. Exemplary dimensions of the canister 170 may include a length L of between 12 and 15 feet, and in the case of a round canister 170 a diameter of between 7 and 13 inches. In an alternative aspect, the canister 170 may have a square cross-section sized to hold the spent nuclear fuel assemblies 150. In some examples, the hazardous-material tank 170 may be sized (e.g., length and width/diameter) for efficient stocking into the borehole 204 and retrieval from the borehole 204. For example, the length may be determined based on the radius dimension of the radiused portion 208 to ensure that the hazardous material tank 170 may move through the radiused portion 208 and into the substantially horizontal portion 210. As another example, the diameter may be determined based on the diameter of one or more casings in the borehole 204, such as the surface casing 220 and the production casing 222.

As shown in fig. 1D, the hazardous-material canister 170 includes a non-conductive ("non-conductive") material in the form of a plurality of non-conductive members 179 mounted to an outer surface of the canister 170. The non-conductive material (non-conductive member 179) is not electrically conductive. Thus, in some aspects, the non-conductive material may prevent a direct electrically conductive ("conductive") electrical path between the canister 170 and, for example, the casing in the borehole in which the canister 170 is stored. Thus, to the extent that the material of the jacket (e.g., carbon steel) and the material of the intermediate portion 175 (e.g., titanium, nichrome, such as alloy 22) form a "battery" (having a conductive liquid, such as brine, in the bore between them), the non-conductive material reduces the likelihood of electrical current connecting the jacket and the tank 170.

In some aspects, the non-conductive member 179 can be a quartz member that is spherical or partially spherical in shape and attached to the outer surface of the intermediate portion 175. Other shapes (e.g., rods, cubes, or partial cubes) are also contemplated for the non-conductive member 179 in accordance with the present disclosure. In addition, other non-conductive materials, such as glass, ceramic, plastic, rubber, may be used instead of quartz. Typically, quartz provides a non-conductive material that does not degrade or decompose within the borehole for hundreds or even thousands of years.

As further shown in fig. 1D, a non-conductive sheath 181 covers at least a portion of the hazardous-material tank 170 to enclose the non-conductive member 179. In some aspects, the non-conductive sheath 181 may be formed of a flexible non-conductive material, such as fiberglass. The non-conductive sheath 181 may provide a friction reducing surface that facilitates easier movement of the canister 170 through one or more bore holes. The non-conductive sheath 181 may also provide some protection for the non-conductive member 179 during movement of the canister 170 through one or more boreholes. In some aspects, the non-conductive sheath 181 may eventually corrode or disintegrate during long term storage of the hazardous material tank 170 in an underground storage reservoir.

Fig. 2A-2C are schematic illustrations of a safe and stable storage underground location, e.g., for long-term (e.g., tens, hundreds, or thousands of years, or more) but retrievable of hazardous materials, during a deposit or retrieval operation, according to an exemplary embodiment of a hazardous materials repository system of the present disclosure. For example, turning to FIG. 2A, this figure illustrates an exemplary hazardous materials repository system 200 during a deposit (or retrieval, as described below) process, such as during the deployment of one or more hazardous materials tanks in a formation. As shown, the hazardous materials repository system 200 includes a borehole 204 formed (e.g., drilled or otherwise formed) from the earth surface 202 through a plurality of subterranean zones 212, 214, 216, and 218. Although the earth's surface 202 is shown as being a land surface, the earth's surface 202 may also be a sea floor or other underwater surface, such as a lake or ocean floor or other surface below a body of water. Thus, the present disclosure contemplates that borehole 204 may be formed below a body of water from a drilling location above or near the body of water.

In this example of the hazardous materials repository system 200, the borehole 204 shown is a directional borehole. For example, the bore 204 includes a generally vertical portion 206, the generally vertical portion 206 being coupled with a rounded or curved portion 208, the rounded or curved portion 208 in turn being coupled to a generally horizontal portion 210. As used in this disclosure, "substantially" in the context of reference to borehole orientation means that it may not be exactly vertical (e.g., exactly perpendicular to the earth's surface 202), or exactly horizontal (e.g., exactly parallel to the earth's surface 202). Further, in some aspects, the substantially horizontal portion 210 may be an angled bore or other directional bore oriented between precisely vertical and precisely horizontal. Further, in some aspects, the substantially horizontal portion 210 may be an angled borehole or other directional borehole oriented to follow the inclination of the formation. As shown in this example, three portions of the bore 204, namely a vertical portion 206, a rounded portion 208, and a horizontal portion 210, form a continuous bore 204 extending into the ground.

The borehole 204 is shown having a surface casing 220, the casing 220 being positioned and disposed to extend around the borehole 204 from the earth's surface 202 into the earth to a depth. For example, the surface shell 220 may be a relatively large diameter tubular member (or a string of members) disposed (e.g., bonded) around the borehole 204 in a shallow layer. As used herein, "tubular" may refer to a member having a circular cross-section, an elliptical cross-section, or other shaped cross-section. For example, in this embodiment of hazardous materials repository system 200, surface shell 220 extends from the surface through surface 212. In this example, surface 212 is a geological formation that includes one or more stratified formations. In some aspects, in this example, surface layer 212 may or may not include a fresh water aquifer, a salt water or brine source, or other source of kinetic water (e.g., water moving through a geological formation). In some aspects, the face shell 212 may isolate the borehole 204 from such live water, and may also provide a hanging location for installing other shell strings in the borehole 204. Further, although not shown, a guide sheath may be provided above surface sheath 212 (e.g., between surface sheath 212 and surface 202 and within surface 212) to prevent drilling fluid from escaping into surface 212.

As shown, production casing 222 is positioned and disposed within borehole 204 downhole of face casing 220. Although referred to as a "production" shell, in this example, shell 222 may or may not be subjected to hydrocarbon production operations. Accordingly, jacket 222 refers to and includes any form of tubular member disposed (e.g., bonded) in borehole 204 downhole of face jacket 220. In some examples of hazardous materials repository system 200, production shell 222 may begin at the end of rounded portion 208 and extend across substantially horizontal portion 210. Jacket 222 may also extend into rounded portion 208 and vertical portion 206.

As shown, adhesive 230 is positioned (e.g., pumped) around shells 220 and 222 in the annular space between shells 220 and 222 and bore 204. Adhesive 230 may, for example, secure casings 220 and 222 (and any other casings or liners of borehole 204) through the subterranean formation below surface 202. In some aspects, adhesive 230 may be provided along the entire length of the shells (e.g., shells 220 and 222 and any other shells), or adhesive 230 may be used along specific portions of the shells if sufficient for a particular borehole 202. The adhesive 230 may also provide an additional containment layer for the hazardous material in the can 100.

The bore 204 and associated casings 220 and 222 may be formed in various exemplary sizes and at various exemplary depths (e.g., true vertical depth or TVD). For example, a guide shell (not shown) may extend down to a TVD of about 120 feet, with a diameter of between about 28 inches and 60 inches. The face shell 220 may extend down to a TVD of about 2500 feet, with a diameter of between about 22 inches and 48 inches. An intermediate shell (not shown) between surface shell 220 and production shell 222 may extend down to a TVD of about 8000 feet with a diameter of between about 16 inches and 36 inches. Production shell 222 may extend generally horizontally (e.g., to surround generally horizontal portion 210) at a diameter of between about 11 inches and 22 inches. The foregoing dimensions are provided as examples only, and other dimensions (e.g., diameter, TVD, length) are contemplated by the present disclosure. For example, the diameter and TVD may depend on the particular geological composition of one or more of the plurality of subterranean zones (212) and 218, the particular drilling technique, and the size, shape, or design of the hazardous materials tank 100 that is to be plugged with the hazardous materials to be stored in the hazardous materials storage reservoir system 200. In some alternative examples, production casing 222 (or other casing in bore 204) may be circular in cross-section, elliptical in cross-section, or some other shape.

As shown, the vertical portion 206 of the borehole 204 extends through the subterranean zones 212, 214, and 216, and in this example, lands in a subterranean zone 219. As described above, the surface layer 212 may or may not include running water. In this example, the subterranean zone 214 below the surface 212 is a hydrodynamic zone 214. For example, the dynamic water layer 214 may include one or more dynamic water sources, such as fresh water aquifers, salt water or brine, or other dynamic water sources. In this example of the hazardous materials repository system 200, the running water may be water that moves through the subterranean zone based on a pressure differential across all or a portion of the subterranean zone. For example, the dynamic water layer 214 may be a permeable geological layer in which water is free to move within the layer 214 (e.g., due to pressure differences or other reasons). In some aspects, the hydrodynamic layer 214 may be the primary source of human available water in a particular geographic area. Examples of rock formations that may comprise the dynamic water layer 214 include porous sandstone and limestone, among other formations.

Other illustrated layers, such as the impermeable layer 216 and the storage layer 219, may include immobile water. In some aspects, the immobile water is water that is not suitable for use by humans or animals or both (e.g., fresh water, salt water, brine). In some aspects, the immobile water may be water that is unable to reach the mobile water layer 214, the earth's surface 202, or both, within 10000 years or more (such as up to 1000000 years) by its movement through the layers 216 or 219 (or both).

In this exemplary embodiment of the hazardous materials repository system 200, below the hydrodynamic layer 214 is an impermeable layer 216. In this example, the impermeable layer 216 may not allow running water to pass through. Thus, the impermeable layer 216 may have a low permeability, such as a permeability on the order of nano-darcy, relative to the dynamic water layer 214. Additionally, in this example, impermeable layer 216 may be a geological layer that is relatively non-malleable (i.e., brittle). One measure of non-ductility is brittleness, which is the ratio of compressive stress to tensile strength. In some examples, the brittleness of impermeable layer 216 may be between about 20MPa and 40 MPa.

As shown in this example, the impermeable layer 216 is shallower (e.g., closer to the surface 202) than the storage layer 219. In this example, the formation that the impermeable layer 216 may include, for example, certain types of sandstone, mudstone, limestone, clay, and slate having permeability and brittleness characteristics as described above. In alternative examples, the impermeable layer 216 may be deeper (e.g., farther from the surface 202) than the storage layer 219. In these alternative examples, impermeable layer 216 may comprise igneous rock, such as granite or basalt.

Below the impermeable layer 216 is a storage layer 218. In this example, the storage layer 218 may be selected as a landing for the substantially horizontal portion 210 that stores the hazardous material for a variety of reasons. The storage layer 218 may be thick relative to the impermeable layer 216 or other layers, for example, between about 100 and 200 feet of total vertical thickness. The thickness of the storage layer 218 may allow for easier placement and directional drilling, allowing the substantially horizontal portion 210 to be easily placed within the storage layer 218 during construction (e.g., drilling). A landing zone may consist of more than one geological layer; for example, it may be comprised of a shale layer above a sandstone layer. If the substantially horizontal portion 210 is formed through a substantially horizontal center of the storage layer 218, the substantially horizontal portion 210 may be surrounded by about 50 to 100 feet of geological formation that includes the storage layer 218. In addition, the storage layer 218 may also have little or no running water, for example, due to the very low permeability of the layer 218 (e.g., on the order of micro-or nano-darcy). Additionally, the reservoir layer 218 may be sufficiently ductile such that the brittleness of the formation including the layer 218 is between about 3MPa and 10 MPa. Examples of rock strata that reservoir 218 may include: shale and anhydrite. Further, in some aspects, hazardous materials may be stored below the storage layer even in permeable formations such as sandstone or limestone if the storage layer has sufficient geological properties to isolate the permeable layer from the flowing water layer 214.

In some exemplary embodiments of the hazardous materials storage reservoir system 200, the reservoir 218 comprises shale. In some examples, the characteristics of the shale may be adapted to the above-described characteristics of the reservoir 218. For example, the shale layers may be suitable for long-term sequestration of hazardous materials (e.g., in the hazardous materials tank 100) and for isolating them from the dynamic water layer 214 (e.g., aquifer) and the surface 202. Shale layers can be found relatively deep on earth, typically 3000 feet or more, and are placed in isolation beneath any fresh water aquifers.

For example, the shale layer may include long-term (e.g., thousands of years) isolated geological properties of the reinforcing material. For example, this property has been illustrated by the long-term (e.g., millions of years) storage of hydrocarbon fluids (e.g., gases, liquids, mixed phase fluids) without these fluids escaping into surrounding layers (e.g., the mobile water layer 214). Indeed, it has been shown that for millions of years or more, shale possesses natural gas, which gives it a proven capacity to store hazardous materials for long periods of time. Exemplary shale layers (e.g., Marcellus shale), Eagle Ford shale, Barnett shale, and other shale layers) have a bedding which contains many redundant sealing layers that have effectively prevented water, oil, and gas movement for millions of years, lack moving water, and can be expected (e.g., based on geological considerations) to seal hazardous materials (e.g., fluids or solids) for thousands of years after they are stored.

The shale layer may also be at a suitable depth, for example between 3000 to 12000 feet TVD. Such depths are typically below groundwater aquifers (e.g., the surface layer 212 and/or the hydrodynamic layer 214). Furthermore, the presence of soluble elements (including salts) in the shale and the absence of these same elements in the aquifer indicate fluid isolation between the shale and the aquifer.

Another characteristic of shale that is particularly advantageous for hazardous material storage on its own is its clay content, which in some aspects provides a greater amount of ductility than is found in other impermeable formations (e.g., impermeable layer 216). For example, shale may be stratified, consisting of thin alternating layers of clay (e.g., between about 20-30% clay by volume) and other minerals. Such compositions may make shale less brittle (e.g., naturally or otherwise) and therefore less brittle than rock formations in impermeable layers (e.g., granite or otherwise). For example, the formation in the impermeable layer 216 may have a suitable permeability for long term storage of hazardous materials, but is too brittle and often breaks. Thus, such formations may not have sufficient sealing properties (as evidenced by their geological properties) for long term storage of hazardous materials.

The present disclosure contemplates that many other layers may be present between or among the illustrated subterranean layers 212, 214, 216, and 218. For example, there may be a repeating pattern of one or more of the dynamic water layer 214, impermeable layer 216, and storage layer 218 (e.g., in a vertical direction). Further, in some examples, the storage layer 218 may be directly adjacent (e.g., in a vertical direction) to the kinetic water layer 214, i.e., without the intervening impermeable layer 216.

Fig. 2A also illustrates an example of a storage operation for hazardous material in a substantially horizontal portion 210 of the borehole 204. For example, as shown, a service line tube 224 (e.g., pipe, coil, cable, or otherwise) may extend into the cased borehole 204 to place one or more (three are shown, but may be more or less) hazardous material tanks 100 into long-term, but in some aspects retrievable, storage in the portion 210. For example, in the embodiment shown in fig. 2A, the work line pipe 224 may include a downhole tool 228 coupled to the tank 100, and with each trip into the borehole 204, the downhole tool 228 may deposit a particular hazardous material tank 100 in the substantially horizontal portion 210.

In some aspects, the downhole tool 228 may be coupled to the canister 100 by a threaded connection. In an alternative aspect, the downhole tool 228 may be coupled to the canister 100 by an interlocking latch such that rotation of the downhole tool 228 may be locked to the canister 100 (or unlocked from the canister 100). in an alternative aspect, the downhole tool 224 may include one or more magnets (e.g., rare earth magnets, electromagnets, combinations thereof, or otherwise) attractively coupled to the canister 100. In some examples, the canister 100 may also include one or more magnets (e.g., rare earth magnets, electromagnets, combinations thereof, or others) having an opposite polarity to the magnets on the downhole tool 224. In some examples, the canister 100 may be made of ferrous materials or other materials that may attract the magnets of the downhole tool 224.

As another example, each canister 100 may be positioned within the bore 204 by a bore tractor (e.g., on a cable or otherwise) that may push or pull the canister into the generally horizontal portion 210 via a motorized (e.g., motorized) motion. As yet another example, each canister 100 may include or be mounted to rollers (e.g., wheels or bearings) such that the downhole tool 224 may push the canister 100 into the cased borehole 204.

In some exemplary embodiments, one or more or both of the canister 100, the drill casings 220 and 222 may be coated with a friction reducing coating prior to the storage operation. For example, by applying a coating (e.g., petroleum-based product, resin, ceramic, or otherwise) to the tank 100 and/or the bore shell, the tank 100 may be more easily moved through the sleeved bore 204 into the substantially horizontal portion 210. In some aspects, only a portion of the drill casing may be coated. For example, in some aspects, the generally vertical portion 206 may not be coated, but the rounded portion 208 or the generally horizontal portion 210 or both may be coated to facilitate easier storage and retrieval of the canister 100.

Fig. 2A also illustrates an example of a retrieval operation of hazardous material in a substantially horizontal portion 210 of the borehole 204. The retrieval operation may be reversed from the deposit operation such that a downhole tool 224 (e.g., fishing tool) may be run into the borehole 204, coupled to the last deposited canister 100 (e.g., threaded, by latch, by magnet, or otherwise), and pull the canister 100 to the surface 202. The downhole tool 224 may make multiple retrieval trips to retrieve multiple canisters from the substantially horizontal portion 210 of the borehole 204.

Each canister 100 may enclose hazardous materials. In some examples, such hazardous materials may be biological or chemical waste or other biological or chemical hazardous materials. In some examples, the hazardous material may include nuclear material, such as spent nuclear fuel or military nuclear material retrieved from a nuclear reactor (e.g., a commercial power reactor or a test reactor). For example, a typical gigawatt nuclear power plant may produce 30 tons of spent nuclear fuel per year. The density of the fuel is typically close to 10(10 mg/cm)³10 kg/litre) so that the nuclear waste amount of one year is about 3m³. Spent nuclear fuel in the form of nuclear fuel pellets can be removed from the reactor without modification. Nuclear fuel pellets are solid and emit little gas except for a short (half-life) period of tritium (13 year half-life).

In some aspects, the storage layer 218 should be able to block any radioactive output (e.g., gas) within the layer 218 even if such output escapes from the tank 100. For example, the storage layer 218 may be selected based on the following conditions: the diffusion time of the radioactive output through the layer 218. For example, the minimum diffusion time for radioactive output out of the escape storage layer 218 may be set to, for example, fifty times the half-life of any particular component of the nuclear fuel pellet. Fifty half-lives as minimum diffusion times will reduce the radiation output by 1X 10^-15And (4) doubling. AsAs another example, setting the minimum diffusion time to thirty half-lives would reduce the radiation output by a billion-fold.

For example, plutonium-239 is often considered a hazardous waste product in spent nuclear fuel due to its long half-life of 24100 years. For this isotope, 50 half-lives would be 120 ten thousand years. Plutonium-239 is low in solubility in water, is non-volatile, and, as a solid, cannot diffuse through the matrix of rock formations including the illustrated storage layer 218 (e.g., shale or other formations). For example, reservoir 218 comprising shale may provide the ability to have such isolated time (e.g., millions of years) as indicated by geological history containing (plugging) gaseous hydrocarbons (e.g., methane and others) for millions of years. In contrast, in conventional nuclear material storage methods, there is a danger that once the packer escapes, some plutonium may dissolve in the bedding including the groundwater.

Turning to fig. 2B, in an alternative embodiment, a fluid 232 (e.g., a liquid or a gas) may be circulated through the bore 204 prior to inserting the canister 100 into the substantially horizontal bore portion 210. In some aspects, the selection of the fluid 232 may depend at least in part on the viscosity of the fluid 232. For example, the fluid 232 may be selected to have a sufficient viscosity to prevent the canister 100 from falling into the generally vertical portion 206. This resistance or impedance may provide a safety factor against the canister 100 being dropped suddenly. Fluid 232 may also provide lubrication to reduce sliding friction between canister 100 and shells 220 and 222. The canister 100 may be transported within a housing filled with a liquid of controlled viscosity, density and lubricating quality. Furthermore, the fluid-filled annular space between the inner diameter of shells 220 and 222 and the outer diameter of the transferred canister 100 represents a passageway designed to dampen any high rate of canister movement, thereby providing automatic passive protection in the unlikely event that the transferred canister 100 becomes disengaged.

In some aspects, the tank 100 may include a flexible or inflatable extension (e.g., mounted to the housing 102) that, in some aspects, may impede the flow of fluid 232 (e.g., air or drilling fluid) through the tank 100 during movement in the borehole 204. The flexible or inflatable extension may also slow the free fall of the canister 100, such as if the latch or transport were to break, for example.

In some aspects, other techniques may be employed to facilitate storage of the canister 100 into the generally horizontal portion 210. For example, one or more of the mounted shells (e.g., shells 220 and 222) may have rails to guide storage tank 100 into bore 202 while reducing friction between the shell and tank 100. The storage tank 100 and the casing (or rail) may be made of materials that easily slide against each other. The surface of the shell may be easily lubricated when bearing the weight of the storage tank 100, or it may be a self-lubricating surface.

Turning to FIG. 2C, another alternative deposit operation is shown. In this exemplary storage operation, a fluid 232 (e.g., a liquid or a gas) may be circulated through the tubular fluid control housing 234 to fluidly push the tank 100 into the substantially horizontal bore portion 210. Fluid 232 may circulate through the end of substantially horizontal portion 210 in fluid control jacket 234 and recirculate back to surface 202 in the annular space between fluid control jacket 234 and jackets 222 and 220. In some examples, each canister 100 may be fluidly pushed in separately. The annular space between fluid control housing 234 and shells 220 and 222 may be filled with a fluid or compressed gas to reverse the flow of fluid 232, for example, to push tank 100 back toward surface 202. In an alternative aspect, two or more canisters 100 may be fluidly pushed through the bore 204 at the same time for storage into the substantially horizontal portion 210. Fluid control jacket 234 may be similar to or identical to production jacket 222. For this case, the separate tubular member may be enclosed in the borehole 202 or within the production casing 222, providing a return path for the fluid 232.

In some aspects, the bore 204 may be formed for the primary purpose of long-term storage of hazardous materials. In an alternative aspect, the borehole 204 may have been previously formed for the primary purpose of hydrocarbon production (e.g., oil, gas). For example, storage layer 218 may be a hydrocarbon containing formation from which hydrocarbons are produced into borehole 204 and to surface 202. In some aspects, storage layer 218 may have been hydraulically fractured prior to hydrocarbon production. Further, in some aspects, production shell 222 has been perforated prior to hydraulic fracturing. In these aspects, prior to storage operations of the hazardous material, the production shell 222 may be repaired (e.g., bonded) to repair any holes made by the piercing process. In addition, any cracks or openings in the adhesive between the casing and the bore hole may also be filled at this time.

For example, in the case of spent nuclear fuel as a hazardous material, a borehole may be formed as a new borehole at a particular location (e.g., near a nuclear power plant) so long as the location also includes a suitable reservoir 218, such as a shale layer. Alternatively, an existing well that has produced shale gas or is abandoned as a "dry" well (e.g., having an organic content low enough that the gas content therein is too low for commercial exploitation) may be selected as the borehole 204. In some aspects, prior hydraulic fracturing of the storage layer 218 through the borehole 204 may have little effect on the hazardous material storage capacity of the borehole 204. However, such prior activities may also confirm the ability of the storage layer 218 to store gases and other fluids for millions of years. Thus, if hazardous materials or an output of hazardous materials (e.g., radioactive gas or otherwise) were to escape from the tank 100 and enter a fracture of the storage layer 218, the fractures may allow the material to spread relatively quickly over a distance commensurate with the size of the fracture. In some aspects, the borehole 202 may have been drilled to produce hydrocarbons, but such hydrocarbon production fails, for example, because the reservoir 218 comprises a formation (e.g., shale or otherwise) that is too ductile to fracture for production, but its ductility facilitates long-term storage of hazardous materials.

The present disclosure, including fig. 2A-2C, describes a hazardous materials storage reservoir system that includes one or more boreholes formed in an underground area to provide long term (e.g., decades, hundreds of years, or even thousands of years) storage of hazardous materials (e.g., biological, chemical, nuclear, or other materials) in one or more underground storage volume storage tanks. The subterranean zone includes a plurality of subterranean layers having different geological layers and properties. The storage tanks may be stored in a particular subterranean formation based on one or more geological properties of the formation, such as low permeability, sufficient thickness, low brittleness, and other properties. In some aspects, a particular subterranean zone includes a shale layer that forms an isolation seal between a storage tank and another subterranean zone that includes flowing water.

Referring generally to fig. 2A-2C, an exemplary hazardous materials storage reservoir system 200 (including the hazardous materials tank 100) may provide multi-layer plugging to ensure that hazardous materials (e.g., biological, chemical, nuclear materials) are sealingly stored in the appropriate subterranean zone. In some example embodiments, there may be at least twelve layers of plugging. In alternative embodiments, a lesser or greater number of blocking levels (blocking layers) may be employed.

First, using spent nuclear fuel as an exemplary hazardous material, the fuel pellets are removed from the reactor without modification. They may be made of sintered uranium dioxide (a ceramic) and may remain solid and emit little gas except for a short (half-life) period of tritium. Most radioisotopes (including tritium) will be blocked in the pellet unless the pellet is exposed to extremely corrosive conditions or other effects that disrupt multilayer blocking.

Second, the fuel pellets are surrounded by the zirconium alloy tubes of the fuel rods, just as in a reactor. As described, these tubes can be installed in the original fuel assemblies, or removed from those assemblies for closer packing. Furthermore, the hazardous-material canister is easy to handle with little risk of damage to the (possibly) brittle zirconium alloy tube.

Third, the tube is placed in a sealed housing of the hazardous material tank. The housing may be a unified structure or a multi-panel structure in which multiple panels (e.g., sides, top, bottom) are mechanically fastened (e.g., by screws, rivets, welding, and others).

Fourth, a material (e.g., solid or fluid or powder) may fill the hazardous material tank to provide further buffering between the material and the exterior of the tank.

Fifth, a hazardous material canister (as described above) is positioned in a bore lined with a steel or other sealed enclosure that, in some examples, extends throughout the bore (e.g., a generally vertical portion, a rounded portion, and a generally horizontal portion). The shell is bonded in place to provide a relatively smooth surface (e.g., as compared to the borehole wall) for the hazardous material tank to be moved through, thereby reducing the likelihood of leakage or rupture during storage or retrieval. In some aspects, the material from which the middle portion 105 of the tank 100 is made (non-shielding material) may be selected to reduce the likelihood of corrosion when emplaced with hazardous waste and during subsequent storage periods. For example, this subsequent period may be 300 years, and may also be 10000 years (and longer and shorter periods).

Sixth, the adhesive that holds the shell in place or helps hold the shell in place may also provide a sealing layer to seal off the hazardous material once it escapes from the canister.

Seventh, the hazardous materials tank is stored in a portion (e.g., a substantially horizontal portion) of the borehole that is within a thick (wide) (e.g., 100-. The reservoir may be selected based at least in part on the geological properties of the formation (e.g., low-velocity water only, low permeability, thickness, suitable ductility or toughness). For example, in the case of rock formations where shale is the reservoir, this type of rock may provide some degree of plugging, since shale has been known to be a seal for hydrocarbon gases for millions of years. Shale may contain brine, but the brine is apparently immobile and not in communication with surface fresh water.

Eighth, in some aspects, the strata of the reservoir may have other unique geological properties that provide another level of plugging. For example, shale often contains reactive components, such as iron sulfide, that reduce the likelihood that hazardous materials (e.g., spent nuclear fuel and its radioactive output) can migrate through the reservoir without reacting in a manner that further reduces the diffusion rate of such output. Furthermore, the storage layer may comprise components, such as clays and organic substances, which generally have a very low diffusivity. For example, shale may be stratified and include thin alternating layers of clay and other minerals. Such stratification of rock formations in a reservoir such as shale may provide the additional seal.

Ninth, the storage layer may be located deeper below than an impermeable layer that separates the storage layer (e.g., in a vertical direction) from the hydrodynamic layer.

Tenth, a storage layer may be selected based on the depth of such layer within the subterranean formation (e.g., 3000 to 12000 feet). Such a depth is typically further (much deeper) below than any layer containing kinetic water, and thus the absolute depth of the storage layer provides an additional blocking layer.

Eleventh, exemplary embodiments of the hazardous materials repository system of the present disclosure facilitate monitoring stored hazardous materials. For example, if the monitored data indicates that a hazardous material is leaking or otherwise (e.g., temperature, radioactivity, or other change) has occurred, or even that the canister is damaged or invaded, the hazardous material canister may be retrieved for repair or inspection.

Twelfth, one or more hazardous material tanks can be retrieved for periodic inspection, adjustment, or repair as needed (e.g., with or without monitoring). Thus, any problem with the canister can be solved without leakage or escape of hazardous material from the unreduced canister.

Thirteenth, even if the hazardous material escapes from the tank and there is no impermeable layer between the leaking hazardous material and the surface, the leaking hazardous material can be blocked in the borehole, at a location where there is no upward path to the surface or aquifer (e.g., dynamic water layer) or other area that could pose a risk to humans. For example, there may be no path directly up (e.g., towards the surface) to the vertical portion of the borehole at the location of the peak, which may be a J-section borehole, the end of an angled borehole, or a vertically undulating borehole.

Fig. 3A-3E are schematic diagrams of an exemplary embodiment of a hazardous materials repository system according to the present disclosure during storage and monitoring operations. For example, FIG. 3A illustrates a hazardous materials repository system 200 in long-term storage operation. One or more hazardous-material tanks 100 are positioned in a generally horizontal portion 210 of the bore 204. A seal 234 is placed in the borehole 204 between the location of the tank 100 in the generally horizontal portion 210 and the opening of the generally vertical portion 206 at the surface 202 (e.g., wellhead). In this example, the seal 234 is placed at the eye-up end of the generally vertical portion 208. Alternatively, the seal 234 may be positioned at another location, upward of the can 100, within the generally vertical portion 206, in the rounded portion 208, or even within the generally horizontal portion 210. In some aspects, the seal 234 may be placed at least deeper than any source of kinetic water within the borehole 204 (such as the kinetic water layer 214). In some aspects, the seal 234 may be formed along substantially the entire length of the vertical portion 206.

As shown, the seal 234 fluidly isolates the volume of the generally horizontal portion 210 of the storage tank 100 from the opening of the generally vertical portion 206 at the surface 202. Thus, any hazardous material (e.g., radioactive material) that does escape the canister 100 may be sealed (e.g., so that liquid, gas, or solid hazardous material does not escape the bore 204). In some aspects, the seal 234 may be a cement plug or other plug that is located or formed in the borehole 204. As another example, the seals 234 may be formed by one or more packers positioned in the borehole 204 that are inflatable or otherwise expandable.

Prior to the retrieval operation (e.g., as discussed with reference to fig. 2A-2B), the seal 234 may be removed. For example, in the case of cement or other permanently disposed seals 234, the seals 234 may be drilled or otherwise milled away. In the case of a semi-permanent seal or a removable seal (such as a packer), the seal 234 may be removed from the borehole 204 by known conventional processes.

Fig. 3B illustrates an exemplary monitoring operation during long-term storage of the tank 100. For example, in some aspects, it may be advantageous or desirable to monitor one or more variables during long-term storage of hazardous materials in the tank 100. In this example of fig. 2B, the monitoring system includes one or more sensors 238 placed in the borehole 204 (e.g., within the substantially horizontal portion 210) and communicatively coupled to a monitoring control system 246 by a cable 236 (e.g., electrical, optical, hydraulic, or otherwise). Although shown within borehole 202 (e.g., inside the casing), sensor 238 may be placed outside the casing, or the casing may be installed in borehole 202 even after the sensor is built into the casing. Sensor 238 may also be placed outside of housing (e.g., housing 220 and/or 222), or outside of fluid control housing 234.

As shown, the sensors 238 may monitor one or more variables such as radiation level, temperature, pressure, presence of oxygen, presence of water vapor, presence of liquid water, acidity (pH), seismic activity, or a combination thereof. Data values relating to these variables may be transmitted along cable 236 to monitoring control system 246. The monitoring control system 246, in turn, may record the data, determine trends in the data (e.g., increased temperature, increased radioactivity levels), transmit the data to other monitoring locations, such as locations of national security or environmental centers, and may automatically recommend actions (e.g., retrieval of the tank 100) based further on such data or trends. For example, an increase in temperature or radioactivity level in the borehole 204 above a certain threshold level may trigger a retrieval recommendation, e.g., to ensure that the tank 100 does not leak radioactive material. In some aspects, there may be a one-to-one ratio of sensors 238 to cans 100. In alternative aspects, there may be multiple sensors 238 per tank 100, or there may be fewer.

Fig. 3C illustrates another exemplary monitoring operation during long-term storage of the tank 100. In this example, the sensor 238 is positioned within a secondary horizontal bore 240 formed separately from the generally vertical portion 206. The secondary horizontal bore 240 may be an exposed (unshrouded) bore through which the cable 236 may extend between the supervisory control system 246 and the sensor 238. In this example, the secondary horizontal bore 240 is formed above the substantially horizontal portion 210 but within the storage layer 218. Thus, the sensors 238 may record data (e.g., radiation level, temperature, acidity, seismic activity) of the storage layer 218. In alternative aspects, the secondary horizontal bore 240 may be formed below the storage layer 218, above a storage layer in the impermeable layer 216, or in other layers. Further, although fig. 3C illustrates the secondary horizontal bore 240 being formed by the same generally vertical portion 206 as the generally horizontal portion 210, the secondary horizontal bore 240 may be formed by a separate vertical bore and a radiused bore.

Fig. 3D illustrates another exemplary monitoring operation during long-term storage of the tank 100. In this example, the sensor 238 is positioned within a secondary vertical bore 242 formed separately from the bore 204. The auxiliary vertical bore 242 may be an encased (jacketed) or exposed (unshrouded) bore through which the cable 236 may extend between the supervisory control system 246 and the sensor 238. In this example, the auxiliary vertical bore 242 extends down to above the substantially horizontal portion 210 but within the storage level 218. Thus, the sensors 238 may record data (e.g., radiation level, temperature, acidity, seismic activity) of the storage layer 218. In alternative aspects, the auxiliary vertical bore 240 may extend downward below the storage layer 218, above a storage layer in the impermeable layer 216, or in other layers. Further, although shown as being placed in the auxiliary vertical bore 242 at a level adjacent the storage level 218, the sensor 238 may be placed anywhere within the auxiliary vertical bore 242. Alternatively, in some aspects, the secondary vertical bore 242 may be built prior to the bore 202, allowing for monitoring by installed sensors 238 during the building of the bore 202. Additionally, the monitoring wellbore 242 may be sealed to prevent the possibility of material leaking into the wellbore 242 having a path to the surface 202.

Fig. 3E illustrates another exemplary monitoring operation during long-term storage of the tank 100. In this example, the sensor 238 is positioned within an auxiliary directional bore 244 formed separately from the bore 204. The secondary directional bore 244 may be an exposed bore through which a cable 236 may extend between the supervisory control system 246 and the sensor 238. In this example, the auxiliary directional bore 244 is disposed within the storage layer 218 adjacent to the substantially horizontal portion 210. Thus, the sensors 238 may record data (e.g., radiation level, temperature, acidity, seismic activity) of the storage layer 218. In alternative aspects, the auxiliary directional bore 244 may be located below the storage layer 218, above a storage layer in the impermeable layer 216, or in another layer. Further, although shown as being placed in the auxiliary directional bore 244 at a level adjacent the storage layer 218, the sensors 238 may be placed anywhere within the auxiliary directional bore 244. In some aspects, the secondary directional bores 244 may be used to retrieve the canister 100, for example, in situations where the bore 204 is inaccessible.

Fig. 4 is a flow chart illustrating an exemplary method 400 associated with storing hazardous materials, such as spent nuclear fuel contained in a spent nuclear fuel assembly. The method 400 may begin at step 402, with step 402 comprising: removing at least one spent nuclear fuel assembly from the nuclear reactor module. For example, the nuclear fuel assembly 150 may become part of a nuclear reactor during reactor operation to ultimately generate electrical energy using fissile nuclear material in the assembly 150. Once the nuclear fuel assembly 150 reaches the end of its life, i.e. the nuclear fuel is spent, the spent nuclear fuel assembly 150 may be removed from the nuclear reactor.

The method 400 may continue at step 404, step 404 including: the spent nuclear fuel assembly is placed into the interior volume of an at least partially unshielded spent nuclear fuel tank (e.g., a tank having shielding for gamma ray transmission on top and bottom ends but not on a middle portion, such as tank 100). For example, the spent nuclear fuel assemblies 150 may be removed directly from the reactor 170 and placed in the hazardous-material tank 100 without any or substantial modification. At least a portion of the hazardous material tank 100, such as the intermediate portion or shell 102, is made of a material that is not shielded from gamma ray transmission but that can provide a barrier to the transmission of nuclear waste solids, liquids, and gases.

In some aspects, a single spent nuclear fuel assembly 150 is placed in the hazardous materials tank 100 due to, for example, the specified size and shape of the internal volume of the tank 100. In alternative aspects, two or more nuclear fuel assemblies 150 may be positioned within the tank 100, for example, vertically and end-to-end. Thus, the hazardous material tank 100 may be sized in height to enclose only a single spent nuclear fuel assembly 150 or multiple spent nuclear fuel assemblies 150 (e.g., the height is a multiple of the height dimension of the assemblies 150). However, the canister 100 may have a cross-sectional dimensional area sized to enclose only a single spent nuclear fuel assembly 150.

In some aspects, spent nuclear fuel assemblies 150 may be stored in one or more other storage locations between steps 402 and 404. For example, the spent nuclear fuel assembly 150 may be moved from a nuclear reactor to a cooling pool (e.g., a spent fuel pool). The spent nuclear fuel assembly 150 may then be moved from the spent fuel pool to a dry cask for further storage. However, neither the spent fuel pool nor the dry cask are designed for long term storage of spent nuclear fuel assemblies 150 (e.g., longer than 40-50 years).

The spent nuclear fuel assembly 150 may then be moved from the dry cask to the hazardous-materials tank 100 for long-term storage, for example, in the hazardous-materials repository 200. Preferably (e.g., for safety and cost considerations), spent nuclear fuel assemblies 150 are not modified between steps 402 and 404. In other words, the spent nuclear fuel assembly 150 is removed from the nuclear reactor in a particular configuration (as shown in fig. 1B) and moved to a spent fuel pool, followed by a dry shielded cask, and then into the tank 100 in the same (or substantially the same) configuration.

In some aspects, due to, for example, the design of the hazardous material tank 100, one or more intermediate storage steps may be omitted (e.g., between a nuclear reactor and long term storage in a hazardous materials repository, as described herein). For example, in some aspects, once the period of storing the assembly 150 in the spent nuclear fuel pool is complete, the spent nuclear fuel assembly 150 may be placed into the hazardous materials tank 100. In some cases, the spent nuclear fuel assembly 150 may be placed in a hazardous materials tank 100 within a pool. Next, the tank 100 (enclosing spent nuclear fuel assemblies 150) may be transported (e.g., within a transport shielded cask) to a well site (hazardous materials repository system 200). The shielding material of the top and bottom portions of the tank 100 may protect or help protect those handling the tank from hazardous materials and radioactive gamma and X-rays during transport. A transport shielding cask surrounding the unshielded middle portion of the canister 100 may provide gamma ray and X-ray shielding. Further, due to the shielding material of the top portion of the can 100, the shipping shield cask may have an open top to facilitate insertion and removal of the can 100 therein.

The method 400 may continue at step 406, step 406 including: enclosing the spent nuclear fuel assembly in an interior volume of a spent nuclear fuel tank. For example, the top portion 106 of the hazardous-material tank 100 may be attached (e.g., welded or otherwise) to the middle portion 102 to physically seal the spent nuclear fuel assembly 150 within the volume 105 of the tank 100.

The method 400 may continue at step 408, with step 408 including: the spent nuclear fuel tanks are moved into an underground hazardous materials repository. Step 408 may be performed, for example, as described with reference to fig. 2A-2C. Step 408 may also include, for example, transporting the tank 100 (or tanks 100) from the nuclear reactor location to a well site, for example, as part of the hazardous materials repository system 200.

Fig. 5 is a schematic diagram of an exemplary controller 500 (or control system) for a hazardous waste monitoring system. For example, the controller 500 may be used for the previously described operations, e.g., as the monitoring control system 246 or as part of the monitoring control system 246. For example, the controller 500 may be communicatively coupled with or part of the hazardous materials repository system described herein.

The controller 500 is intended to include various forms of digital computers, such as a Printed Circuit Board (PCB), processor, digital circuit, or other form of being part of a vehicle. Additionally, the system may include a portable storage medium, such as a Universal Serial Bus (USB) flash drive. For example, a USB flash drive may store an operating system and other applications. The USB flash drive may include input/output components such as a wireless transmitter or a USB connector that may be plugged into a USB port of another computing device.

The controller 500 includes a processor 510, a memory 520, a storage device 530, and an input/output device 540. Each of the components 510, 520, 530, and 540 may be interconnected using a system bus 550. Processor 510 is capable of processing instructions for execution within system 500. The processor may be designed using any of a variety of architectures. For example, processor 510 may be a CISC (Complex instruction set computer) processor, RISC (reduced instruction set computer) processor, or MISC (minimal instruction set computer) processor.

In one implementation, the processor 510 is a single-threaded processor. In another implementation, the processor 510 is a multi-threaded processor. The processor 510 is capable of processing instructions stored in the storage 520 or in the storage device 530 to display graphical information for a user interface on the input/output device 540.

The storage 520 stores information within the controller 500. In one implementation, the storage 520 is a computer-readable medium. In one embodiment, the storage 520 is a volatile storage unit. In another implementation, the memory 520 is a non-volatile storage unit.

The memory device 530 is capable of providing mass storage for the controller 500. In one implementation, the storage device 530 is a computer-readable medium. In various different embodiments, the storage device 530 may be a floppy disk device, a hard disk device, an optical disk device, a tape device, a flash memory, a Solid State Device (SSD), or a combination thereof.

The input/output device 540 provides input/output operations for the controller 500. In one embodiment, the input/output device 540 includes a keyboard and/or pointing device. In another embodiment, the input/output device 540 includes a display unit for displaying a graphical user interface.

The described features can be implemented in digital electronic circuitry, or in computer hardware, firmware, software, or in combinations of them. The apparatus can be implemented in a computer program product tangibly embodied in an information carrier, e.g., in a machine-readable storage device for execution by a programmable processor; method steps may be performed by a programmable processor executing a program of instructions to perform functions of the described embodiments by operating on input data and generating output. The described features can be implemented advantageously in one or more computer programs that are executable on a programmable system including at least one programmable processor coupled to receive data and instructions from, and to transmit data and instructions to, a data storage system, at least one input device, and at least one output device. A computer program is a set of instructions that can be used, directly or indirectly, in a computer to perform a certain activity or bring about a certain result. A computer program can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment.

Suitable processors for the execution of a program of instructions include, by way of example, both general and special purpose microprocessors, and the sole processor or one of multiple processors of any kind of computer. Generally, a processor will receive instructions and data from a read-only memory or a random access memory or both. The essential elements of a computer are a processor for executing instructions and one or more memories for storing instructions and data. Typically, a computer will also include, or be operatively coupled to communicate with, one or more mass storage devices for storing data files; such devices include magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and an optical disc. Storage devices suitable for tangibly embodying computer program instructions and data include all forms of non-volatile storage, including, for example, semiconductor memory devices, such as EPROM, EEPROM, Solid State Drives (SSDs), and flash memory devices; magnetic disks, such as internal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and the memory may be supplemented by, or incorporated in, ASICs (application-specific integrated circuits).

To provide for interaction with a user, the various features can be implemented on a computer having a display device such as a CRT (cathode ray tube) or LCD (liquid crystal display) or LED (light emitting diode) display for displaying information to the user and a keyboard and a pointing device such as a mouse or a trackball by which the user can provide input to the computer. Additionally, such activities may be accomplished through a touch screen flat panel display and other suitable mechanisms.

The features can be implemented in a control system that includes a back-end component, such as a data server, or that includes a middleware component, such as an application server or an internet server, or that includes a front-end component, such as a client computer having a graphical user interface or an internet browser, or any combination of them. The components of the system can be connected by any form or medium of digital data communication, such as a communication network. Examples of communication networks include a local area network ("LAN"), a wide area network ("WAN"), peer-to-peer networks (with dedicated or static members), grid computing facilities, and the internet.

Although this document contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features specific to particular implementations. Certain features that are described herein in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain cases, multitasking and parallel processing may be advantageous. Moreover, in the embodiments described above, the separation of various system components should not be understood as requiring such separation in all embodiments, but rather it should be understood that the described program components and systems can generally be integrated together in a single software product or packaged into multiple software products.

A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure. For example, the exemplary operations, methods, or processes described herein may include more or fewer steps than those described. Further, the steps in such exemplary operations, methods, or processes may be performed in a different order than that described or illustrated in the figures. Accordingly, other implementations are within the scope of the following claims.