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i <br />3.2.2 Erosion Gulley in Right Abutment Groin <br />During Site Visits 1 and 2 a large erosion gulley was observed in the right abutment groin of the <br />dam. The gully appeared to have been formed where surface waters collected and concentrated <br />in the groin area and the resulting concentrated flows eroded embankment material down to the <br />liner, which subsequently ripped and degraded in some isolated spots. While the rip in the liner <br />at this location on the dam would not allow water infiltrating the tailing to escape to <br />groundwater, the tear in the liner could allow water to infiltrate more than necessary into the <br />downstream portion of the dam embankment and could subsequently elevate the phreatic <br />surface. Additionally, further erosion to the embankment itself would be expected to occur over <br />time, exacerbating the situation. The erosion gulley as it appeared on Site Visit 2 is depicted in <br />Figure 6. <br />Figure 6 Site Visit 2, Right Abutment Groin Erosion <br />Gulley before Repairs, Looking Upstream from Near Toe <br />San Luis Project Miller Geotechnical Consultants <br />Tailing Dam Data Report 12 February 2014 <br />