Beyond one million years: The intrinsic radiation hazard of high-level nuclear wastes

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Exposure time in hours for getting the annual ICRP dose constraint of 0_3 mSv as a function of time at three distances from POLLUX-8 cask assemblies, neglecting the shielding of the cask

Gamma dose rate (mSv/h) at three distances from a POLLUX-8 cask loaded with 8 UO2 fuel assemblies, neglecting the shielding of the cask

Density and HVL for various materials depending on the energy of the gamma rays

Transmission factors for energies 0_944 MeV and 0_312 MeV in R7T7 glass waste forms of radii 21 cm and 5 cm

Dose rate computation coefficients for the German spent fuel of Table 1

Highest gamma energies in the (4n + 2) and (4n + 1) chains_ The weighted averages values are based on the data obtained from Japan Atomic Energy Agency [15,16,17,18]

Elemental activity ratios (at 10 000 years) and chain activity ratios (at one million years) for French VHLW

Relative contributions from the three actinide chains to the gamma dose from a block of unshielded eight UO2 fuel assemblies (same assemblies as mentioned in Table 1)

Main contributors to the gamma dose rate from SF as a function of time The original calculations were based on LWR fuel but, for the past 105 years, say, they apply to any U-fuel, as the differences among uranium fuel types smooth out_ in million years for the configuration of Table 1_ The (4n + 2) elements are denoted in bold and the (4n + 1) elements are denoted in italics