TMI Criticality Studies: Lower Vessel Rubble and Analytical Benchmarking

Westfall, R.M.; Knight, Jack; Fox, Patricia; Hermann, O.W.; Turner, James C.

doi:10.2172/5750006

Cited by 2 publications

(2 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Calculation results, in conjunction with available information from examinations showing that the fuel was oxidized and mixed with structural material, provided confirmation that the parameters used to monitor during defueling and shipping were adequate. [61,62,63] • Pyrophoricity -Prior to lowering the RPV water level for debris removal operations, there were concerns about possible pyrophoric reactions from cutting and removal of debris containing metallic Zircaloy, uranium/zirconium alloy, and zirconium hydride. Theoretical evaluations, prior experience, and separate effect tests were completed to show that conditions to cause such reactions were limited; and examination information was used to confirm that such conditions were not present at TMI-2.…”

Section: Tmi-2 Post-accident Evaluationsmentioning

confidence: 99%

“…Concerns about adverse effects, such as chemical reactions or recriticality, associated with injecting this hydrogen peroxide were addressed using laboratory testing. [61,62] In summary, examination information was essential for successful TMI-2 cleanup efforts. The importance of this experience was emphasized during the workshop, TMI-2 Knowledge Transfer and Relevance to Fukushima Meeting (See Appendix E of [4]).…”

Section: Tmi-2 Post-accident Evaluationsmentioning

confidence: 99%

See 1 more Smart Citation

U.S. Efforts in Support of Examinations at Fukushima Daiichi: 2019 Evaluations

Amway¹,

Andrews²,

Basu³

et al. 2019

View full text Add to dashboard Cite

Much is still not known about the end-state of core materials in each unit that was operating on March 11, 2011 at the Fukushima Daiichi Nuclear Power Station (Daiichi). Information obtained from Daiichi is required to inform Decontamination and Decommissioning (D&D) activities, improving the ability of the Tokyo Electric Power Company Holdings, Incorporated (TEPCO Holdings) to characterize potential hazards and to ensure the safety of workers involved with cleanup activities. This document, which has been updated to include Fiscal Year 2019 (FY2019) information, summarizes results from a U.S. effort to review Daiichi information and extract insights to enhance the safety of existing and future nuclear power plant designs. This U.S. effort, which was initiated in 2014 by the Department of Energy Office of Nuclear Energy (DOE-NE), is completed by a group of experts in reactor safety and plant operations that identify examination needs and evaluate recent Daiichi examination data to address these needs. Each year, annual reports are issued that document significant safety insights being obtained in areas of special emphasis. For FY2019, the areas emphasized by the expert panel include component performance, radionuclide surveys and sampling, debris end-state location, combustible gas effects, and plant operations and maintenance. In addition to reducing uncertainties related to severe accident modeling progression, these insights have and continue to be used to update guidance for severe accident prevention, mitigation, and emergency planning. Reduced uncertainties in modeling the events at Daiichi improve the realism of reactor safety evaluations that inform future D&D activities. In addition, the process established by this U.S. effort provides an example that Japan may wish to implement in future international efforts to support D&D.

show abstract

Section: Tmi-2 Post-accident Evaluationsmentioning

confidence: 99%