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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.”
J. D. Simpson, J. K. Hoffer, L. R. Foreman
Fusion Science and Technology | Volume 21 | Number 2 | March 1992 | Pages 330-333
Safety; Measurement and Accountability; Operation and Maintenance; Application | doi.org/10.13182/FST92-A29766
Articles are hosted by Taylor and Francis Online.
We have examined two of the variables that affect the beta-layering process in which nonuniform layers of solid deuterium-tritium (DT) are driven toward uniformity by beta-decay induced sublimation. For these experiments, a 9 mm diameter polycarbonate sphere was partially filled with a 50-50 mix of DT liquid, frozen, and then held at 17 K. We measured the equilibration time constant τ as functions of solid layer thickness, 4He exchange gas pressure, and age. Solid layer thicknesses ranged from 200 µm to 650 µm, exchange gas pressures from 0 to 600 torr, and age from 0 to 104 days. Results show a significant final solid layer anisotropy with exchange gas pressures above 5 torr, and τ values that increased with age by 0.01 min/day for 200 µm-thick layers, and by 0.5 min/day for 650 µm-thick layers. The time constant is shown to be a weak function of exchange gas pressure.