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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.”
D. R. Juliano, D. N. Ruzic, D. Hill, K. A. Werley
Fusion Science and Technology | Volume 29 | Number 2 | March 1996 | Pages 269-276
Technical Paper | Divertor System | doi.org/10.13182/FST96-A30713
Articles are hosted by Taylor and Francis Online.
Sufficient neutral atom and molecular throughput is essential for the steady-state operation of the proposed Tokamak Physics Experiment tokamak. To predict the throughput, the B2 edge-plasma fluid code and the DEGAS Monte Carlo neutral transport code were coupled globally. For the day 1 low-power (17.5-MW) operation condition, the recycling coefficient for both codes matched at 0.985, implying that for every 1000 ions striking the divertor plate, 15 are ultimately removed down the pump duct. The neutral molecular density was 2.52 ± 0.15 × 1019/m3, giving a throughput of 92.6 ±5.6 Torr · ℓ/s. Varying the scrape-off length for the plasma extending into the gap between the baffle and the plate from 0 to 2 cm decreased the throughput by a factor of >2. Moving the strike point away from the gap at first increases the throughput by lessening the pumping efficiency of the plasma in the gap. As the plasma is moved even farther away, the throughput drops due to a lack of source term for neutrals entering the pumped region. Illustrating the importance of moving the source term, moving the strike point away from the gap but retaining the original plasma in the gap lowers the throughput by a factor of 10. Altering the curvature of the baffle has little effect on the neutral solution.