Deep borehole disposal (DBD) has been suggested as an option for disposing spent nuclear fuel in a number of countries, including several countries that are subject to international safeguards. DBD presents some distinct challenges for safeguards compared to a conventional mined geological repository (MGR), including the ability to verify declared design information about the borehole. The ability to verify a borehole's design is crucial for assuring that spent fuel or other accountable nuclear materials are disposed as declared in a borehole of known and verifiable design. This study reviews existing commercial off-the-shelf (COTS) borehole inspection tools currently used by the drilling industry, and evaluates the capabilities of those COTS inspection tools against how well they can meet potential needs and requirements of Design Information Verification (DIV) inspections for international safeguards. The study provides recommendations for several promising COTS borehole inspection tools that might be used for DIV safeguards inspections and recommends possible modifications and future testing
Deep borehole disposal (DBD) has been suggested as an option for disposing spent nuclear fuel in a number of countries, including several countries that are subject to international safeguards. While potential benefits of deep borehole disposal include increased safety, reduced cost, and greater flexibility, the method could also impact the implementation of international safeguards. DBD presents some unique safeguards challenges compared to a conventional MGR. These challenges include 1) verifying borehole design below the surface; 2) strong reliance on CoK up to and including disposal; 3) limitations on the ability to observe or verify successfully emplaced canisters; and 4) successfully monitoring a closed and sealed DBD facility over the long term. In some cases, such challenges may prove easier for a DBD facility than for a conventional MGR, others more difficult, and still others may require new methodologies (or existing methodologies newly applied to safeguards). Long-term monitoring in particular might be somewhat less onerous.