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DOE announces NEPA exclusion for advanced reactors
The Department of Energy has announced that it is establishing a categorical exclusion for the application of National Environmental Policy Act (NEPA) procedures to the authorization, siting, construction, operation, reauthorization, and decommissioning of advanced nuclear reactors.
According to the DOE, this significant change, which goes into effect today, “is based on the experience of DOE and other federal agencies, current technologies, regulatory requirements, and accepted industry practice.”
E. Tucker, J. Gilligan
Fusion Science and Technology | Volume 26 | Number 4 | December 1994 | Pages 1265-1274
Technical Paper | First-Wall Technology | doi.org/10.13182/FST94-A30311
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Energetic (> 10-keV) particles incident on divertor plate surfaces may penetrate the vapor shield formed under extremely high heat flux conditions (> 1010 W/m2). In this case, the total energy transmission factor f through the vapor shield can increase drastically, which leads to more surface damage. A one-dimensional time-dependent coupled magnetohydrodynamic-radiation transport code MAGFIRE, originally used in modeling the vapor shield development under a blackbody radiation source, has been modified to include a charged-particle source. The sources used to model a disruption are monoenergetic beams of electrons and/or deuter-ons with any given incident heat flux and energy per particle. An electron source (≤20 keV) will eventually (for times ≤10 µs) be completely absorbed by the vapor resulting in f converging to the same f (for times ≥100 µs) as an equivalent ion heat flux source. Results show that in fact all three sources converge (at ∼100 µs) to the same steady-state value of f for any given heat flux. Results also show that steady-state f decreases for increasing heat fluxes on a carbon surface. Non-steady-state f, however, depends on total incident beam energy fluence and electron energy per particle. The energetic electron spectrum incident on divertor plates during a disruption needs to be measured on large tokamaks so that reliable simulation can be done for International Thermonuclear Experimental Reactor (ITER)-like conditions.