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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.”
Ronald J. Onega, Bill M. Su
Fusion Science and Technology | Volume 2 | Number 4 | October 1982 | Pages 667-686
Technical Paper | Blanket Engineering | doi.org/10.13182/FST82-A20806
Articles are hosted by Taylor and Francis Online.
Calculations of the steady-state neutron, photon, and temperature distributions as well as the transient thermal distribution following a major plasma disruption (MPD) in the first wall and blanket region of an engineering type of controlled thermonuclear reactor was made. A canister blanket design was considered and both the incident neutron and secondary gamma-ray heating were used in calculating the volumetric heat source rate. An average value of the volumetric heat source rate was calculated to be ∼0.5 MW/m3 and the neutron wall loading was 2. 38 MW/m2. After steady-state conditions were obtained, major plasma disruption times of 10 and 24 ms were assumed for the transient calculations. For each case, a constant velocity model was assumed for the surface heat flux impinging on the first wall during an MPD. Neutronic studies using the ANISN code provided volumetric heat source rates that were used to do the thermal analysis. With these volumetric heat source rates obtained, a heat conduction code, HEATING5, was run for the steady-state temperature distribution. Using the steady-state temperature distribution as an initial condition, HEATING5 was run again for the transient thermal study, which included the surface heat flux due to the disruption, together with a volumetric heat source rate resulting from the eddy currents induced in the wall following an MPD. Results show that there is a possibility of melting portions of the first wall if the disruption time of 10 ms is used, while no melting is possible for the 24-ms case; however, a maximum transient temperature of ∼1000°C on the first wall does occur. The temperature in the blanket region remained the same as before the MPD since the transient takes place so rapidly that the effects were felt most by the first wall. The average number of abortions allowed before failure of the first wall was 200 thermal cycles for the 24-ms case.