Progress on Canisters for Radioactive Waste Transport, Storage and Disposal in Boreholes - 23528

Safe disposal of high-level waste and spent nuclear fuel remains a key objective to global energy portfolio health, with many countries keen on developing solutions over the next decade. Of these proactive countries, many are taking an interest in Deep Isolation for its use of directional drilling technology that would emplace nuclear waste in canisters deep underground in vertical, deviated, or horizontal boreholes. The Deep Isolation borehole solution offers a safe, modular solution where waste can be emplaced on- or near-site, thus reducing risk and cost of waste transportation. Lastly, a standardized canister design allows for process and cost efficiencies for disposal solutions of any size. Deep Isolation has spent the past several years collaborating with NAC International (NAC) on a drill hole canister (DHC) designed for the deep geological disposal of pressurized water reactor (PWR) fuel assemblies in a borehole. During the 2022 Waste Management Symposium, Deep Isolation and NAC presented the DHC preliminary design, demonstrating confidence in the structural, thermal, shielding, and criticality safety analyses for loaded DHCs in storage, transportation, and disposal configurations. Over the past year, significant progress has been made to enhance DHC system safety, lifting and handling operations, manufacturability, and economic viability. Deep Isolation commissioned the Nuclear Advanced Manufacturing Research Centre (NAMRC) to conduct a design for manufacture review and NAC updated the DHC design based on this review and continued development. Additional collaboration with partners to review lifting and handling operations, along with planned emplacement and retrieval processes, resulted in changes to the DHC lift adapter, improving safety and reliability. The results of the NAMRC design for manufacture review provided valuable insights into the manufacturing process that NAC factored into DHC design changes, resulting in significant savings for Deep Isolation and its customers per deep borehole repository project while simplifying canister manufacturing using standardized dimensions and manufacturing practices. These changes are not expected to impact the canister loading capacity, safety basis, or diameter of the borehole needed for waste disposal. A collaborative investigation with Deep Isolation partners was performed in the past year regarding the use of various potential emplacement rigs commonly used in the oil and gas industry. While Deep Isolation's 2019 demonstration employed a wireline for the emplacement of a sealed source-size canister, simulating a Department of Energy - Hanford Site cesium or strontium capsule, in a borehole, the use of coiled tubing has since been explored to provide additional functionality, including increased emplacement and retrieval forces for the larger and heavier PWR disposal canisters. The investigation into the use of coiled tubing also resulted in an opportunity to improve upon the planned interface of the canister via a lift adapter with existing drilling technologies. The lift adapter will be installed atop the canister prior to facilitating disposal operations. The previous bolt-on design has been replaced with a lift adapter that is both easy to assemble and compatible with generic lifting and handling equipment. Fabrication of a mockup canister based on the updated PWR canister design is underway, with delivery expected in early 2023. Upon receipt, Deep Isolation is planning for functional testing of the redesigned lift adapter interface to support continued use of the PWR canister. (authors)