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CLEAN SMART bill reintroduced in Senate
Senators Ben Ray Luján (D., N.M.) and Tim Scott (R., S.C.) have reintroduced legislation aimed at leveraging the best available science and technology at U.S. national laboratories to support the cleanup of legacy nuclear waste.
The Combining Laboratory Expertise to Accelerate Novel Solutions for Minimizing Accumulated Radioactive Toxins (CLEAN SMART) Act, introduced on February 11, would authorize up to $58 million annually to develop, demonstrate, and deploy innovative technologies, targeting reduced costs and safer, faster remediation of sites from the Manhattan Project and Cold War.
R. W. Conn, T. Y. Sung, M. A. Abdou
Nuclear Technology | Volume 26 | Number 4 | August 1975 | Pages 391-399
Technical Paper | Reactor | doi.org/10.13182/NT75-A24440
Articles are hosted by Taylor and Francis Online.
The induced radioactivity and afterheat in five recently presented fusion reactor blanket designs have been calculated. These designs differ in the choices of structural material, coolant, and neutron multiplier. Nevertheless, the radioactivity levels at shutdown after a 2-yr operation are within a factor of 4 of each other and are clustered at ∼1 Ci/W(th). However, the long-term radioactivity (>200 yr) is greatest for niobium structures and least for aluminum. For niobium, the level of long-term activity is ∼5 × 10−5 Ci/W(th), whereas for aluminum, the level drops to ∼10−7 Ci/W(th) just several weeks after shutdown. This last result will be modified by the inclusion of trace elements and impurities. Afterheat levels are found to vary from to 5% of the thermal operating power, depending on design and the choice of structural material. Importantly, however, the afterheat power density is only ∼0.2 W/cm3 at most and this is roughly a factor of 10 to 60 less than the afterheat power density in fast breeder reactors. Biological hazard potential (BHP) values are calculated for all designs by the pessimistic approach of dividing the activity in Ci/kW(th) by the lowest maximum permissible concentration value, in Ci/km3 of air, given in U.S. Atomic Energy Commission rules, Title 10, Part 20. In all cases, the BHP nevertheless drops below 1 km3/ kW(th) 20 yr after shutdown following a 2-yr operation. The key isotopes contributing to radioactivity, afterheat, and BHP are listed for future reference.