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NEWMONT <br /> GOLDCORP <br /> liner surface." The 1996 letter from Golder Associates (Appendix A to Memo <br /> EG 19-08) indicates the testing was performed in accordance with ASTM <br /> Standard Test Method D5321, not allowing the sample to consolidate completely <br /> under normal load, thereby not allowing the excess pore water pressures to <br /> dissipate. However, many of the test samples involved soil liner fill (SLF, <br /> essentially clay) next to the geomembrane in the test sample. It would seem <br /> excess pore pressure and water would be more likely on the SLF side of the test <br /> sample and not on the coarser drain cover fill (DCF) side of the sample. Please <br /> provide a more explicit discussion of how a reduced friction angle (with respect to <br /> a dry interface between the geomembrane and ore to be placed in the test cell) <br /> was selected to account for process solution on top of the geomembrane in this <br /> slope stability analysis. <br /> The footprint of the study cell will be lined using an 80 mil double- <br /> sided textured linear low density polyethylene (LLDPE) <br /> geomembrane. The liner will be placed on prepared subgrade, <br /> comprised of leached ore, and overlain with crushed ore. As the ore <br /> materials placed above and below the liner classify as gravels with <br /> low fines content and permeability on the order of 1 E-3 centimeters <br /> per second (cm/s), the ore is considered free-draining and unable to <br /> generate any excess pore water pressure under the maximum ore <br /> placement rate. Soil liner fill (SLF), with a maximum permeability of <br /> 1 E-6 cm/s, will not be used to construct the geomembrane liner <br /> system for the study cell; therefore, the interface shear tests that <br /> included SLF are not considered representative of the configuration <br /> to be constructed. Instead, interface shear test #5 on the <br /> configuration that included gravel materials above and below the <br /> liner (i.e., drain cover fill [DCF] and low volume solution collection fill <br /> [LVSC]) is considered representative and was used for the analyses. <br /> A piezometric head was modeled at one foot above the liner to <br /> account for the process solution on the lined surface (resulting in a <br /> reduction to the interface strength). The permeability of the ore <br /> (above and below the liner) is orders of magnitude greater than the <br /> solution application rate; therefore the modelled piezometric level is <br /> conservative. <br /> 6) Implementation Schedule: The response is not adequate. The response narrative <br /> implies the study could continue after two years. Informal telephone discussions <br /> with CC&V personnel agreed on a commitment to a two year limit to begin <br />