Wireless Sensor Platform for Dry Spent Fuel Cask Monitoring

Nuclear power plants regularly generate spent fuel that must be stored on the decade timescale. Often this is done in dry nuclear waste storage casks. Long-term monitoring would provide data that improves the safe maintenance of stored spent fuel. This requires measuring the conditions within waste casks using a self-contained sensor system. Radiation Monitoring Devices, Inc. is developing a system that detects damaged fuel rod cladding by sensing and quantifying the amount of 85Kr present using a diamond sensor. A potential means for power and data transfer through the cask wall uses an ultrasonic transmission method. The work described here advances the prototype toward inclusion in a specific model fuel cask, the NUHOMS® 32 PTH1 manufactured by Orano (formally, Areva Transnuclear, Inc.). The results include extensive radiological modeling studies, an estimation of the leaked activity due to 85Kr after a cladding breach (~ 1013Bq) derived from a literature review, a design for a prototype, and the characterization of a diamond detector at room temperature and in the presence of 85Kr.