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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.”
Laila A. El-Guebaly
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1475-1480
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-A29549
Articles are hosted by Taylor and Francis Online.
The International Thermonuclear Experimental Reactor (ITER) is designed to operate in two phases; physics and technology. The prime function of the shield is to protect the TF magnets. The predominant radiation limits are the nuclear heat load to the magnet and the end-of-life dose to the electrical insulator. These limits are specified by the magnet designers as 65 kW and 5×109 rads. Detailed shielding analysis has been performed and necessary machine modifications have been proposed during the conceptual design phase (1987–1990) in order to meet the magnet radiation limits. The shield is designed to satisfy the neutronics, thermal hydraulics, and mechanical design requirements. The reference shield consists of 316 SS structure and water coolant. A 5 cm thick back layer with special materials, such as W, Pb, and B4C, is considered outside the vacuum vessel to reduce the magnet damage. Two regions with critical shielding space are identified in ITER, the inboard and divertor regions. This paper presents the various options for the shield design based on a variety of shielding materials and summarizes the different analyses carried out to guide the shield design.