The Open Collections website will be undergoing maintenance on Wednesday December 7th from 9pm to 11pm PST. The site may be temporarily unavailable during this time.

British Columbia Mine Reclamation Symposium

Mine rock stockpile reclamation trial, Detour Lake Mine : Initial geotechnical, ecological, and hydrological performance Harrington, J. S.; Mendoza, C. A.; Straker, J.; Baker, T.; McMahen, K.; Raizman, V.; Lyle, K.

Abstract

Guidance for beneficial strategies for landform design and progressive reclamation is being developed at Detour Lake Mine (northern Ontario) by monitoring and evaluating the large-scale, 10-ha Test Cover Trial on a mine rock stockpile. The design and construction of the Test Cover Trial are described in the companion paper by Cash et al., which comprises a reclamation cover placed on 13 different trial plots with varying slope angle, aspect, cover thickness, surface grading, and revegetation prescription. This paper describes preliminary results from monitoring that is ongoing to evaluate the geotechnical, ecological, and hydrological performance of the Test Cover Trial and the relative performance of different cover treatments. Site visits are used to record geotechnical, ecological, and hydrological observations. Instrumentation includes a meteorological station and multi-level installations of soil-moisture sensors. Monitoring data are used for numerical modelling of the reclamation cover hydrological regime. To date, large-scale slope instabilities have not been observed in the reclamation cover, contrary to expectations. Most erosion and related deposition of reclamation cover material occurred over the first year following construction. There are appreciable differences in performance between different trial plots. Plots with the steepest and shallowest slope angles, the thinnest cover, or corrugated surface grading exhibit the most erosion. Vegetation survival is correlated with surface grading, cover bulk density, peat content, and slope aspect. Vegetation is becoming established in erosional rills and gullies and on some depositional fans. Instrumentation data indicate that the reclamation cover generally remains unsaturated. Preliminary hydrologic modelling indicates that the reclamation cover decreases net percolation and sensitivity analyses suggest that net percolation may vary due to climate and vegetation effects. Overall, the geotechnical performance of many cover treatments is exceeding expectations, vegetation performance is different than expected due to appreciable plant removal by birds, and hydrological performance is similar to design expectations.

Item Citations and Data

Rights

Attribution-NonCommercial-NoDerivatives 4.0 International