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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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DOE issues new NEPA rule and procedures—and accelerates DOME reactor testing
Meeting a deadline set in President Trump’s May 23 executive order “Reforming Nuclear Reactor Testing at the Department of Energy,” the DOE on June 30 updated information on its National Environmental Policy Act (NEPA) rulemaking and implementation procedures and published on its website an interim final rule that rescinds existing regulations alongside new implementing procedures.
Eze Wills, Norman Roderick, Patrick McDaniel
Nuclear Science and Engineering | Volume 93 | Number 3 | July 1986 | Pages 291-307
Technical Paper | doi.org/10.13182/NSE86-A17758
Articles are hosted by Taylor and Francis Online.
A method for solving particle transport problems has been developed. In this method the particle flux is expressed as a linear and separable sum of odd and even components in the direction variables. Then a Bubnov-Galerkin projection technique and an equivalent variational Raleigh-Ritz solution are applied to the second-order transport equation. A dual finite element basis of polynomial splines in space and spherical harmonics in angle is used. The general theoretical and numerical problem formalism is carried out for a seven-dimensional problem with anisotropic scattering, time dependence, three spatial and two angular variables, and with a multigroup treatment of the energy dependence. The boundary conditions for most physical problems of interest are dealt with explicitly and rigorously by a classical minimization (variational) principle. Finally, the computational validation of the method is obtained by a computer solution to the monoenergetic steady-state air-over-ground problem in a cylindrical (r, z) geometry and with an exponentially varying atmosphere.