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Cripple Creek&Victor Phone(719)689-2977 Gold Mining Company Fax(719)689-3254 PO Box 191 100 N 3rd ANGLOGOLD ASHANTI Victor,CO80860-0191 ANGLOGOLD ASHANTI (COLORADO) CORP. week during the injection program. If, during the injection program, the survey data indicates a total vertical displacement rate of 1-inch per week or greater, then injection activities should be terminated and the injection pressures revised. In accordance to the AMEC letter dated 17 December, 2009, the Factor of Safety (FoS) for the Valley Leach Facility (VLF) will remain at or greater than the minimum acceptable value of 1.5 as long as the injection guidelines presented in the letter are followed.The injection guidelines are: 1.The injection wells should be located a minimum of 20 feet from the crest of any ore benches. Only wells that will have deep (+100 feet) injection depths can be located closer than 20 feet from the bench crest; 2. Injection pressures in the upper 70 feet should not exceed %:of the overburden pressure. Higher injection pressures can be used for depths greater than 70 feet, but should not exceed the overburden pressure; and 3. Injection pressures should always be closely monitored and controlled to avoid any local instabilities. 3. Electrical Resistivity Characterization and Monitoring Figures 1 and 2 show the positions of the nine HJ wells along the westernmost edge of the 9925' elevation of Phase 2. Also shown are the positions of seven additional bore holes distributed over the HJ target area. As part of CC&V's commitment to monitoring the HJ project and ensuring the safe stable operation of the VLF, these holes are will be used to install a network of subsurface electrodes that will be used to monitor solution profiles during injection events using electrical resistivity techniques. HydroGeophysics Inc. (HGI), a geophysical firm specializing in resistivity monitoring, has been contracted to work in concert with MRS during the injections. As the saturation of the pore space is increased during the injection, the electrical resistivity of the heap decreases. Hence, by monitoring the resistivity between various combinations of electrodes it will be possible for HGI to determine the preferred flow directions at each injection depth as well the proximity of these flow paths to the surface of the VLF. HGI has previously demonstrated the benefits of electrical resistivity characterization and monitoring in support of the HJ process at Newmont, (Rucker, 2009a; Rucker et al., 2009b) establishing very close ties to Metal Recovery Solutions (MRS) that have continued through the commercialization of HJ. HGI will use the subsurface electrodes in conjunction with a network of surface electrodes deployed on the surrounding areas to track the migration of fluid during each injection event. Since the data is gathered in real time, if HGI determines that solution migration paths are not as desired it will be possible to relay this to MRS operators so that immediate action can be taken. As shown in Figures 1 and 2 the network of subsurface electrodes installed in the monitoring bore holes will surround injection wells labeled HJ-2, HJ-3, and HJ-4. The numeric designation in the well ID denotes the position of the well in the target area rather than the treatment order - the aforementioned will actually be treated first. Data generated from injections in these wells will provide an avenue to reconcile physical operations with analytical relationships and establish a robust baseline to ensure complete process control during stimulation of subsequent wells.