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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 22 | Number 1 | August 1992 | Pages 124-134
Technical Paper | D-3He/Fusion Reactor | doi.org/10.13182/FST92-A30062
Articles are hosted by Taylor and Francis Online.
The implications of the D-3He fuel cycle on shielding design are investigated for tokamak power reactors of the ARIES/Apollo class. The prime function of the shield is to protect the superconducting magnets against radiation. A variety of shield options is examined, and the various shields are optimized for the D-3He neutron spectrum. The results demonstrate the relative merits of the various materials as a function of the shield thickness. In the first wall/shield, low-activation structural materials (such as Tenelon, modified HT-9, silicon carbide composites, and carbon-carbon composites) were employed to reduce the radioactive inventory and increase the safety margin in case of accidents. A comparison between the different shield options based on detailed neutronics, environmental/safety, and economic assessments has led to the selection of the reference shield design. The first-wall/shield structure is made of an elementally tailored ferritic steel (MHT-9), and the thermal energy is converted through an organic coolant at 44% efficiency. The safety features of the low-activation steel shield, along with the low neutron production in the D-3He fuel cycle, enable the ARIES-III/Apollo design to achieve acceptable environmental and safety characteristics.