Ontario Power Generation's Response to the Joint Review

Serge Clement 1011170042-TM-G2100-0001-01
Tetra Tech
December 23, 2011
Recommendations
The estimated inflow through the uncracked concrete liner for the top 190 m (sealed design) is 0.2 USGPM.
Based on conservative analyses carried out for the cracked liner, it has been determined that a 1 in 2,500 year
seismic event would result in inflows less than 2 USGPM through the shaft lining due to crack formation. A 1 in
100,000 year seismic event would result in an inflow of approximately 50 USGPM. In the unlikely event that the
hydraulic conductivity of the concrete liner is increased to 1×10 -6 m/s (what if scenario 2), the inflows may reach
150 USGPM. This value can be considered an upper bound limit for the inflow.
References
[1]. Data Review Report-Hydrogeological Test Information. Golder Document No. 1011170042-REP-G2060-
0001-00, January 2011.
[2]. NWMO Shaft and Repository Dewatering – Results of Groundwater Flow Model. Golder Document No.
1011170042-TM-G2090-0001-A, April 2011.
[3]. Shaft Seismic Analyses. Golder Document No. 1011170042-TM-G2140-0002-A, June 2011.
[4]. Wang, K., Jansen, D.C., Shah, S.P., and Karr, A.F., 1997. Permeability Study of Cracked Concrete.
Cement and Concrete Research 27.3 (1997): 381-393.
[5]. Lepech, M., Li, V. C., 2005. Water Permeability of Cracked Cementitious Composites. Paper 4539 of
Compendium of Papers CD ROM, Eleventh International Conference on Fracture, Turin, Italy, March
2005.
[6]. AMEC Geomatrix Inc., 2011, OPG’s Deep Geologic Repository for Low and Intermediate Level Waste
Seismic Hazard Assessment. NWMO DGR-TR-2011-20, March 2011.
J.L. Carvalho, Ph.D., P.Eng. C.M. Steed, M.A.Sc., P.Eng.
Principal Principal
JLC/CMS/jlc/co
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