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Leaching of Nirex Reference Vault Backfill cement by clay, granite and saline groundwaters

  • Rita G. W. Vasconcelos (a1), Andres Idiart (a2), Neil C. Hyatt (a1), John L. Provis (a1) and Claire L. Corkhill (a1)...

Abstract

For the UK geological disposal facility (GDF) concept in a high strength crystalline rock, Nirex Reference Vault Backfill (NRVB) has been considered to use as a cementitious backfill material. The lifetime performance of this high pH material is required to be extremely long, and as a consequence of the interaction with the geological environment (e.g. groundwater), the backfill material will evolve and age with time. In this paper, we present the results of a leaching experiment, where NRVB is placed in contact with three different groundwater compositions representative of granitic, clay and saline groundwater for 35 days. Some differences were observed related with the mineralogy. X-ray Diffraction results showed the formation of more ettringite, mainly in the NRVB samples leached in clay and saline groundwater. An increase of the pH was also observed in the NRVB samples leached with the three different ground waters, being these results in accordance with the reactive transport modelling performed.

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*Corresponding author: c.corkhill@sheffield.ac.uk

References

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[1]Radioactive Waste Management (2015). Geological Disposal: The 2013 Derived Inventory. Report no. NDA/RWM/120.
[2]Nuclear Decommissioning Authority (2010a). Geological Disposal: Generic Disposal Facility Designs. Report no. NDA/RWMD/048.
[3]Nuclear Decommissioning Authority (2010b). Geological Disposal: Near-Field Evolution Status Report. Report no. NDA/RWMD/033.
[4]Francis, A. J., Cather, R., and Crossland, I. G. (1997). Nirex Safety Assessment Research Programme: Development of the Nirex Reference Vault Backfill; Report on Current Status in 1994. Report no: S/97/014.
[5]Vasconcelos, R.G.W, Beaudoin, N., Hamilton, A., Hyatt, N.C., Provis, J.L., Corkhill, C.L. (2018). Characterisation of a high pH cement backfill for the geological disposal of nuclear waste: The Nirex Reference Vault Backfill. Appl. Geochem. 89, 180189.
[6]Gascoyne, M. (2002). Influence of grout and cement on groundwater composition. POSIVA Working Report 2002-07, Posiva Oy.
[7]Vinsot, A., Mettler, S., and Wechner, S. (2008). In situ characterization of the Callovo-Oxfordian pore water composition. Phys. Chem. Earth, vol. 33, no. SUPPL. 1.

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