The dilemma of spent fuel management policies and policy drift - Relationship between policy changes and changes in terms and concepts of spent nuclear fuel -

As with the storage of all radioactive materials, the storage of spent nuclear fuel (SF) and high-level radioactive waste (HLW) must conform to safety requirements. Safety aspects like safe enclosure of radioactive materials, safe removal of decay heat, nuclear criticality safety and avoidance of unnecessary radiation exposure must be achieved throughout the storage period. The implementation of these safety requirements can be achieved by dry storage of SF and HLW in casks as well as in other systems such as dry vault storage systems or spent fuel pools, where the latter is neither a dry nor a passive system. After the events of Fukushima, the advantages of passively and inherently safe dry storage systems have become more obvious. TÜV and BAM, who work as independent experts for the competent authorities, present the licensing process for sites and casks and inform about spent nuclear fuel management and issues concerning dry storage of spent nuclear fuel, based on their long experience in these fields. All safety relevant issues like safe enclosure, shielding, removal of the decay heat or behavior of cask and building under accident conditions are checked and validated with state-of-the-art methods and computer codes before the license approval. It is shown how dry storage systems can ensure the compliance with the mentioned safety criteria over a long storage period. Exemplarily, the process of licensing, erection and operation of selected German dry storage facilities is presented.

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How to Improve the Public Engagement and Deliberation on Spent Nuclear Fuel Management - Lessons from the French System -

Journal of Social Science ◽

10.22418/jss.2018.12.57.2.259 ◽

2018 ◽

Vol 57 (2) ◽

pp. 259-294

Author(s):

Hong Chan Chun

Keyword(s):

Nuclear Fuel ◽

Public Engagement ◽

Spent Nuclear Fuel ◽

Fuel Management ◽

The Public

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Chemical Effects at the Reaction Front in Corroding Spent Nuclear Fuel

MRS Proceedings ◽

10.1557/proc-985-0985-nn01-03 ◽

2006 ◽

Vol 985 ◽

Author(s):

Jeffrey A. Fortner ◽

A. Jeremy Kropf ◽

James L. Jerden ◽

James C. Cunnane

Keyword(s):

Transition Zone ◽

Nuclear Fuel ◽

Spent Nuclear Fuel ◽

Aqueous Environment ◽

Spent Fuel ◽

Aqueous Corrosion ◽

Reduction Potentials ◽

Chemical Effects ◽

Before And After ◽

X Ray Absorption

AbstractPerformance assessment models of the U. S. repository at Yucca Mountain, Nevada suggest that neptunium from spent nuclear fuel is a potentially important dose contributor. A scientific understanding of how the UO2 matrix of spent nuclear fuel impacts the oxidative dissolution and reductive precipitation of Np is needed to predict the behavior of Np at the fuel surface during aqueous corrosion. Neptunium would most likely be transported as aqueous Np(V) species, but for this to occur it must first be oxidized from the Np(IV) state found within the parent spent nuclear fuel. In this paper we present synchrotron x-ray absorption spectroscopy and microscopy findings that illuminate the resultant local chemistry of neptunium and plutonium within uranium oxide spent nuclear fuel before and after corrosive alteration in an air-saturated aqueous environment. We find the Pu and Np in unaltered spent fuel to have a +4 oxidation state and an environment consistent with solid-solution in the UO2 matrix. During corrosion in an air-saturated aqueous environment, the uranium matrix is converted to uranyl (UO22+) mineral assemblage that is depleted in Np and Pu relative to the parent fuel. The transition from U(IV) in the fuel to a fully U(VI) character across the corrosion front is not sharp, but occurs over a transition zone of ∼ 50 micrometers. We find evidence of a thin (∼ 20 micrometer) layer that is enriched in Pu and Np within a predominantly U(IV) environment on the fuel side of the transition zone. These experimental observations are consistent with available data for the standard reduction potentials for NpO2+/Np4+ and UO22+/U4+ couples, which indicate that Np(IV) may not be effectively oxidized to Np(V) at the corrosion potential of uranium dioxide spent nuclear fuel in air-saturated aqueous solutions.

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The Need for Integrating the Back End of the Nuclear Fuel Cycle in the United States of America

MRS Advances ◽

10.1557/adv.2018.231 ◽

2018 ◽

Vol 3 (19) ◽

pp. 991-1003 ◽

Cited By ~ 3

Author(s):

Evaristo J. Bonano ◽

Elena A. Kalinina ◽

Peter N. Swift

Keyword(s):

United States ◽

Nuclear Fuel ◽

United States Of America ◽

Spent Nuclear Fuel ◽

Fuel Cycle ◽

Nuclear Fuel Cycle ◽

The United States ◽

Spent Fuel ◽

Dry Storage ◽

The Us

ABSTRACTCurrent practice for commercial spent nuclear fuel management in the United States of America (US) includes storage of spent fuel in both pools and dry storage cask systems at nuclear power plants. Most storage pools are filled to their operational capacity, and management of the approximately 2,200 metric tons of spent fuel newly discharged each year requires transferring older and cooler fuel from pools into dry storage. In the absence of a repository that can accept spent fuel for permanent disposal, projections indicate that the US will have approximately 134,000 metric tons of spent fuel in dry storage by mid-century when the last plants in the current reactor fleet are decommissioned. Current designs for storage systems rely on large dual-purpose (storage and transportation) canisters that are not optimized for disposal. Various options exist in the US for improving integration of management practices across the entire back end of the nuclear fuel cycle.

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