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Bob Oswald-DRMS <br />7/28/09 <br />Page 2 of2 <br />While it is possible that the slump could accelerate to failure, it is more likely that displacement of <br />the slump will slow to equilibrium as material is re-adjusted, without the occurrence of a rapid, <br />large-scale event. This judgment is based on the cohesive nature of the slide materials, and the <br />history of displacement. The relatively large displacements that have been observed at this <br />slump have not led to rapid, large-scale slope failure. <br />The consequences of slope failure, although considered unlikely, would be minor. The worst <br />case scenario would place a few tens of cubic yards of soil and rock at the bottom of the South <br />Pit that would block the drainage and require removal to re-establish the South Pit drainage. The <br />Pitch site has some heavy construction equipment and operating personnel, and could react <br />quickly to remove any material from the slump. Again the more likely scenario is that the slump <br />will slow to equilibrium or quasi-equilibrium over time. <br />We will continue to monitor the slump by ongoing survey methods and field reconnaissance. <br />Additional monitoring or stabilization efforts are not recommended at this time. <br />Your second comment had to do with some of springs and seeps noted on Table 2 of the annual <br />report. Springs IC-4, IC-10, IC-12, CFS and CFS-2 were shown on Figures 3 of the report. <br />However depending on the print quality of that figure, they may have been difficult to locate. <br />We've include an updated version of Figure 3 with the background topography screened to make <br />the various features standout. Springs IC-4, IC-10 and IC-12 are all located along Indian Creek <br />between the Indian Creek Dump Toe Drain and the Sediment Pond. Springs CFS and CFS-2 are <br />located in the South wall of the North Pit. All of the springs mentioned have shown increased <br />flows over the past five years due to increased precipitation and recharge of groundwater. <br />Similarly, the piezometers installed in the area of the Pinnacle Mine workings (P4 -P10) all have <br />shown a gradual increase in water levels since 2005. <br />I trust that this provides the necessary information / response to address your questions outlined <br />in your letter. Please let me know if you have further questions or require additional information. <br />Sincerely yours, <br />me C?J>e <br />Alan D. Cox <br />Homestake Mining Company of California <br />Cc: S. Shuey, DRMS-Grand Junction <br />R. Chase, Barrick-SLC <br />P. DeDycker, ARCADIS, Denver <br />V. Kelso, HMC-Sargents <br />P.O. Box 98 / Highway 605, Grants, NM 87020 Tele: (505) 287-4456 FAX: (505) 287-9289