| Autor: |
A. Dierckx, M. Van Gompel, M. Aertsens, P. De Cannière, N. Maes |
| Rok vydání: |
2008 |
| Předmět: |
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| Zdroj: |
Physics and Chemistry of the Earth, Parts A/B/C. 33:S61-S66 |
| ISSN: |
1474-7065 |
| DOI: |
10.1016/j.pce.2008.10.060 |
| Popis: |
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 H 14 CO 3 - ) in Boom Clay and the upper lying sands of Eigenbilzen or Voort have been determined by pulse injection experiments on cores taken from different depths in the Mol-1 borehole (Belgium). The results for HTO and iodide have been reported previously and the present paper completes this study with H 14 CO 3 - . In the range from 191 m to 281 m depth (Below Drilling Table), the Boom Clay Formation can be considered as homogeneous with respect to the hydraulic conductivity and the transport parameters of H 14 CO 3 - . The value of the vertical hydraulic conductivity is around 2.5–3 × 10−12 m/s. The average apparent diffusion coefficient Dapp of H 14 CO 3 - in the direction perpendicular to the bedding plane is (6 ± 3) × 10−11 m2/s. The product ηR of the diffusion accessible porosity η and the retardation factor R of H 14 CO 3 - is 0.26 ± 0.03, lying between the value of iodide (ηR = 0.16) and of HTO (ηR = 0.37). Due to anion exclusion, iodide has a lower porosity than HTO. Because of the lower ηR value of an anion as iodide, a slight sorption of H 14 CO 3 - cannot be excluded (R ⩽ 0.26/0.16 ≈ 1.6). |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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