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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.”
S. Sharafat, S.P. Grotz, M. Z. Hasan, T. K. Kungi, C. P. C. Wong, E. E. Reis, THE ARIES TEAM
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 895-900
Advanced Reactor | doi.org/10.13182/FST91-A29458
Articles are hosted by Taylor and Francis Online.
The ARIES tokamak-reactor design study is a multi-institutional project investigating several different visions of the tokamak as a commercial power reactor. The ARIES-I reactor design incorporates modest extrapolation of existing physics with advanced technology in the fusion power core (FPC) design. Use of aggressive technology such as high-field magnets and low-activation silicon-carbide (SiC) composites help to make ARIES-I an attractive reactor with excellent safety characteristics. The ARIES-I reactor uses a double-null poloidal-field (PF) divertor for particle exhaust and impurity control. Control of the edge-plasma density and temperatures has reduced the energy of the incident particles at the divertor to ∼20 eV, which is below the self-sputtering threshold for the tungsten target surface material. The target is constructed of SiC composite tubes with a 2-mm-thick plasma-sprayed coating of tungsten on the plasma-facing side and a 0.5-mm chemical-vapor deposited (CVD) coating of SiC on the back. The divertor is cooled by helium at lOMPa with inlet/outlet temperatures of 350°/650°C. In removing the divertor surface heat flux of 4.5 MW/m2, a design safety factor of 1.8 is achieved. The divertor has a waste disposal rating of 0.10 (see text for definition), thus allowing Class-C shallow land burial, and a site boundary dose of 11.2 rem during an accidental release. Isotopic tailoring of the tungsten and target replacement every two years is necessary to achieve these safety characteristics.