The search for potential storage sites for radioactive waste requires the drilling of reconnaissance boreholes that must subsequently be plugged and sealed. The aim of this project was to propose a methodological approach, based on in situ experiments and laboratory characterization, for sealing boreholes in crystalline rocks, specifically granite. This consisted of defining a product with appropriate properties for the fractured rock intersected by the boreholes. The grout defined during the characterization stage was composed of calcic bentonite (mineral bulk to provide low permeability), a hydraulic binder (for good cohesion) and bitumen (to improve adherence and deformability). The grout was tested in situ at the Jouac site, Massif Central, France. Effectiveness of the grout in situ was characterized by comparing the permeability of the fracture network before and after injection. This study has revealed the need for drawing up a better characterization procedure for potential sealing materials for guarantee that they are tailored to the specific requirements. The monitoring of plug installation also requires further consideration, as does the need to carry out more in situ tests than at present.
Bibliographic Reference: EUR 17657 EN (1997) 181pp., FS, ECU 33.00
Availability: Available from the (2)
ISBN: ISBN 92-828-0790-8
Record Number: 199710988 / Last updated on: 1997-09-16
Original language: en
Available languages: en