TY - JOUR

T1 - Vertical distribution of H14CO_3 transport parameters in Boom Clay in the Mol-1 borehole (Mol, Belgium)

AU - Aertsens, Marc

AU - Van Gompel, Marc

AU - De Cannière, Pierre

AU - Maes, Norbert

AU - Dierckx, A.

N1 - Score = 10

PY - 2008/10

Y1 - 2008/10

N2 - An important question for the performance assessment of a potential geological waste disposal site for radioactive waste in Boom Clay is: can the Boom Clay be considered as a homogeneous clay layer from the point of view of its migration properties? Therefore, the hydraulic conductivity and the transport parameters of tritiated water (HTO) and two critical radionuclides (129I- and H14CO3-) in Boom Clay and the upper lying sands of Eigenbilzen or Voort have been determined on cores taken from different depths in the Mol-1 borehole.
In the range from 191 m to 281 m depth, the Boom Clay Formation can be considered as homogeneous with respect to the hydraulic conductivity and the transport parameters of H14CO3-. The value of the vertical hydraulic conductivity is around 2.5 - 3 10-12 m/s. The average apparent diffusion coefficient Dapp of H14CO3- in the direction perpendicular to the bedding plane is (6 3) 10-11 m2/s. The product R of the diffusion accessible porosity and the retardation factor R of H14CO3- is 0.26 0.03, lying between the value of iodide (R = 0.16) and of HTO (R = 0.37). Due to anion exclusion, iodide has a lower porosity than HTO.

AB - An important question for the performance assessment of a potential geological waste disposal site for radioactive waste in Boom Clay is: can the Boom Clay be considered as a homogeneous clay layer from the point of view of its migration properties? Therefore, the hydraulic conductivity and the transport parameters of tritiated water (HTO) and two critical radionuclides (129I- and H14CO3-) in Boom Clay and the upper lying sands of Eigenbilzen or Voort have been determined on cores taken from different depths in the Mol-1 borehole.
In the range from 191 m to 281 m depth, the Boom Clay Formation can be considered as homogeneous with respect to the hydraulic conductivity and the transport parameters of H14CO3-. The value of the vertical hydraulic conductivity is around 2.5 - 3 10-12 m/s. The average apparent diffusion coefficient Dapp of H14CO3- in the direction perpendicular to the bedding plane is (6 3) 10-11 m2/s. The product R of the diffusion accessible porosity and the retardation factor R of H14CO3- is 0.26 0.03, lying between the value of iodide (R = 0.16) and of HTO (R = 0.37). Due to anion exclusion, iodide has a lower porosity than HTO.

KW - bicarbonate

KW - diffusion accessible porosity

KW - apparent diffusion coefficient

KW - dispersion coefficient

KW - boom clay

KW - hydrualic conductivity

UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/ezp_94897

UR - http://knowledgecentre.sckcen.be/so2/bibref/5594

U2 - 10.1016/j.pce.2008.10.060

DO - 10.1016/j.pce.2008.10.060

M3 - Article

VL - 33, Supplement 1

SP - S61-S66

JO - Physics and Chemistry of the Earth

JF - Physics and Chemistry of the Earth

SN - 1474-7065

T2 - Clays in natural and engineered barriers for radioactive waste confinement

Y2 - 17 September 2007 through 20 September 2007

ER -