Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-24T13:12:39.860Z Has data issue: false hasContentIssue false

Clay-Based Grouting Into the EDZ for the Vault Sealing

Published online by Cambridge University Press:  10 February 2011

Y. Sugita
Affiliation:
Japan Nuclear Cycle Development Institute (JNC), Ibaraki, Japan, sugita@tokai.jnc.go.jp
T. Fujita
Affiliation:
Japan Nuclear Cycle Development Institute (JNC), Ibaraki, Japan
K. Masumoto
Affiliation:
Kajima corporation, Chofu, Tokyo, Japan
N. Chandler
Affiliation:
Atomic Energy of Canada Limited (AECL), Pinawa, Manitoba, Canada, R0E IL0
Get access

Abstract

In the Japanese concept for the disposal of the high-level radioactive wastes (HLW), the potential pathways for radioactive contaminant transport would be sealed by a combination of tunnel plug, backfilling and grouting. The candidate material for these engineered barriers would be bentonite or a bentonite-based mixture taking into consideration long-term stability of the seals. Two tests of bentonite grouting for sealing an excavation damage zone (EDZ), that exists in the rock in the immediate vicinity of the tunnel, were conducted in the granitic rock at Atomic Energy of Canada Limited's (AECL's) Underground Research Laboratory (URL). One test was the trial for the development of grouting procedure and the evaluation of grouting effectiveness, and the second test was a demonstration of the grouting around the clay-block bulkhead of the Tunnel Sealing Experiment (TSX). In the trial, the injection proportion of 4.0% of grout slurry was the most efficient. The result of the seepage test showed that grouting resulted in a reduction of hydraulic conductivity of the EDZ in the floor of the tunnel. In the demonstration, although the hydraulic pulse test didn't indicate that the grouting significantly reduced the rock hydraulic conductivity, the test was a useful site-scale demonstration of bentonite grout injection for the purpose of EDZ sealing around a tunnel bulkhead.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1 Japan Nuclear Cycle Development Institute, H12 Project to Establish Technical Basis for HLW Disposal in Japan - Project Overview Report 2 -, the Draft Second Progress Report on Research and Development for the Geological Disposal of HLW in Japan, JNC TN1400 99-010, 1999.Google Scholar
2 Chandler, N., Dixon, D., Gray, M., Hara, K., Cournut, A. and Tillerson, J., An in situ Demonstration of Technologies for Vault Sealing, Proc. 19th Annual Conference of Canadian Nuclear Society, 1998.Google Scholar
3 Chandler, N., Kozak, E. and Martin, C., Connected Pathways in the EDZ and the potentialfor flow along tunnels, Proc. EDZ Workshop, Int. Conf. Deep Geological Disposal of Radioactive Waste, Canadian Nuclear Society, 1996, p. 2534.Google Scholar
4 Ramey, H. J., Agarwal, R. G. and Martin, I., Analysis of ëSlug Testí or DTS Flow Period Data, J. Can. Petroleum Technology, vol.14, 1975, p. 3747.Google Scholar
5 Sugita, Y. and Fujita, T., Clay Grouting Experiment at the Kamaishi Mine, Proc. 27th Symposium on Rock Mechanics, 1996, p. 276280. (in Japanese)Google Scholar
6 Masumoto, K., Sugita, Y., Fujita, T. and Chandler, N., Trial of Bentonite Grouting into the EDZ at AECL's Underground Research Laboratory, Proc. 29th Symposium on Rock Mechanics, 1999, p. 3642.Google Scholar