Enhanced network smart markers (ENSMs) were installed at Teck's Highland Valley Copper (THVC) mine in an actively moving slope where standard downhole instrumentation is often damaged within weeks of installation and rendered inoperable. The ENSMs were used to monitor downhole deformation in the active shear zone and provide movement and water pressure data after the standard inclinometer and vibrating wire piezometer (VWP) installations were sheared. ENSMs provide a new approach to monitoring

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... ubsurface deformation. As with any new technology, ENSM performance needed to be evaluated and validated for the data to be deemed reliable. The trial conducted at THVC was set up such that the ENSMs were installed along with traditional technology (inclinometers and VWPs). This enabled a direct comparison between the ENSMs and inclinometer/VWPs for the trial at THVC. ENSMs were installed as downhole arrays, attached to inclinometer pipe and standard piezometers in two boreholes located on the Valley pit southeast wall. As the Valley pit mining sequence progressed downslope of the boreholes, deformations and pore pressure readings were recorded. This paper presents comparative deformations taken over a period of several months recorded by the ENSM system, versus readings recorded using a traditional inclinometer system. Additionally, pore pressure readings recorded by the ENSM system are compared to data recorded by traditional grouted in-place vibrating wire piezometers. Deformations and pore pressure measurements generally correlate well, and discrepancies between the systems are discussed. There were many learnings from the trial, but the main success was following significant amounts of shearing in the wall, the ENSM system continued to yield data below the shear zone after the traditional instruments had been severed. This allowed for deformation and pressure data to be monitored below the shear for a longer period than was possible using traditional downhole slope monitoring methods.