S. Himmelstein | June 16, 2023
The U.K. government is committed to delivering deep geological disposal of nuclear waste by means of a mined geological disposal facility, with a preference for delivery at a single site. A recent study explored the potential for the directional borehole disposal technology advanced by California-based Deep Isolation to improve the long-term management of high-activity waste in the U.K.
The directional borehole solution places corrosion-resistant canisters containing radioactive waste and spent fuel deep underground. It deploys widely used directional-drilling technology to access stable and isolated host rocks, supported by site characterization techniques to ensure geologic isolation and patented canister technology to transport and manage fuel assemblies.
Schematic of a deep horizontal drillhole repository. Source: Deep Isolation
While this disposal route cannot completely negate the need for a geological disposal facility, it can still play a key role in dealing with the national nuclear waste inventory. With appropriate packaging, most if not all of the heat-generating waste could potentially be secured in boreholes. According to Deep Isolation, this will account for 96% of forecast radioactivity levels in 2200.
The company has received funding from the U.K. Department for Energy Security and Net Zero to engineer a corrosion-resistant canister capable of safely encapsulating spent fuel assemblies for disposal within deep borehole repositories 1 km to 3 km underground. Each canister would dispose of spent fuel that has enabled the generation of 132 million kWh of low carbon electricity, representing a saving of nearly 27,000 tons of carbon dioxide per canister.
