Khaled Ahmad AlTurkestani
King Faisal School, Riyadh, Saudi Arabia
The deep-borehole concept is a promising approach for nuclear waste disposal. It is essentially a very deep hole drilled vertically in granite bedrock for storage of nuclear waste. Studies of the deep-borehole storage facility have yielded positive results. However, selection of the most effective sealant for the deep-borehole is an issue that remains to be resolved.
This research evaluated two possible materials for plugging the borehole: granite and concrete. Three scenarios were studied using different mathematical models. The first scenario assumed that the radionuclides diffused through dry granite and concrete. The second scenario assumed that the radionuclides diffused through stagnant water contained in the interconnected voids in the sealant. The third scenario assumed that the difffusion occurred through pressure-driven bulk water flow. Results for all three cases were positive. It appears that the amount of leaking radioactive waste can be expected to be very low in all three scenarios studied. Furthermore, it appears that granite and concrete are suitable materials for plugging the deep-borehole.