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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.”
A. Y. Ying, A. R. Raffray, M. A. Abdou
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1481-1486
ITER | Proceedings of the Ninth Topical Meeting on the Technology of Fusion Energy (Oak Brook, Illinois, October 7-11, 1990) | doi.org/10.13182/FST91-A29550
Articles are hosted by Taylor and Francis Online.
This paper addresses the thermal transport issues associated with a loss of flow accident (LOFA) for US ITER solid breeder blanket. Two LOFA scenarios were considered. For a LOFA due to a simultaneous catastrophic pump failure, the coolant temperature reaches its boiling point within only about 15 – 20 seconds. This scenario appears extremely unlikely and should be better characterized through a probability risk assessment study in order to determine to what extent corrective actions such as the use of backup pump should be taken. For a LOFA due to loss of power to the coolant pumps, the resulting flow transient is characterized by considering the effect of fluid inertia and pump inertia. Once a determination of the flow coastdown has been made, the temperature histories of blanket elements and coolant are analyzed using lumped parameter techniques. The results of the analyses indicate that the rate of coolant temperature rise due to the heat (generated and/or stored) transferred from the solid breeder area is strongly dependent on the transient flow behavior. If the coolant pump can be designed with a sufficiently large pump inertia (with an inertia time constants of about 1.5 s or more), the coolant temperature can stay under its boiling point for several minutes to allow for corrective action to be implemented. As an added safety measure, it seems prudent to include in the design a system of expansion volumes and/or safety valves for accommodating coolant pressure transients.