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Trump administration begins overhaul of the NRC
Hanson
Since the president's inauguration in January, the Trump Administration has been on course to make big changes at the Nuclear Regulatory Commission to realize its goals of deregulation, energy dominance, and deployment of advanced reactors. Given the many executive orders (EOs) and the work the Department of Government Efficiency has done in cutting the federal workforce, it was a surprise that NRC commissioner Christopher Hanson was dismissed on Friday, according to a statement Hanson posted on his LinkedIn profile early Monday.
Hanson said in the post that President Trump terminated his position “without cause, contrary to existing law and long-standing precedent regarding removal of independent agency appointments.”
G. Perret, M. F. Murphy, F. Jatuff, J-Ch. Sublet, O. Bouland, R. Chawla
Nuclear Science and Engineering | Volume 163 | Number 1 | September 2009 | Pages 17-25
Technical Paper | doi.org/10.13182/NSE08-55
Articles are hosted by Taylor and Francis Online.
Radial distributions of the total fission rate and the 238U-capture-to-total-fission (C8/Ftot) ratio were measured in SVEA-96+ and SVEA-96 Optima2 assemblies during the LWR-PROTEUS program. Fission rates predicted using MCNPX with JEFF-3.1 cross sections underestimated the measured values in the gadolinium-poisoned pins of the SVEA-96 Optima2 assembly; similarly, C8/Ftot ratios were overestimated in some gadolinium-poisoned pins of the SVEA-96+ assembly. A considerable effort was invested at the Paul Scherrer Institut to explain the discrepancies in gadolinium pins, without success. Recently, gadolinium cross sections were measured at the Rensselaer Polytechnic Institute by Leinweber et al. and differed significantly from current library values. ENDF/B-VII.0 gadolinium cross sections have currently been modified to include the new measurements, and these data have been processed with NJOY to yield files usable by MCNPX. Fission rates in the gadolinium-poisoned fuel pins of the SVEA-96 Optima2 pins were increased by 1.4 to 2.0% using the newly produced cross sections, yielding to a better agreement with the experimental values. Predicted C8/Ftot ratios were decreased on average by 1.7% in both clustered and unclustered groups of gadolinium-poisoned fuel pins of the SVEA-96+ assembly correcting the overpredictions previously reported in the clustered gadolinium pins. Earlier reported discrepancies observed in PROTEUS integral experiments, between measured and calculated reaction rates in the gadolinium-poisoned pins, might thus be due to inaccurate gadolinium cross sections. The PROTEUS results support the new thermal and epithermal gadolinium data measured by Leinweber et al.