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ameO <br />September 9, 2009 <br />Mr. Timm Comer <br />Environmental Manager <br />AngloGold Ashanti (Colorado) Corp <br />Post Office Box 191 <br />100 North Third Street <br />Victor, Colorado 80860 <br />Re: Phase 5 PSSA Ore Slope Change <br />Dear Timm: <br />AMEC Earth and Environmental (AMEC) has prepared this letter presenting a recent modification in the <br />Phase 5 PSSA grading plan. In the original Phase 5 design, the Phase IV ore slope (which forms the <br />western side of the PSSA) is to be re-graded to a 2.5 horizontal (H): 1 vertical (V) slope to support <br />geomembrane deployment. However, when the re-grade slope limits were surveyed in the field, the crest <br />of the slope fell very close to the new steel solution header pipes (located on the 9775 bench) at three <br />locations. In order to provide more clearance between the header pipes and the slope crest, the re-grade <br />slope was increase from 2.51-1: 1V to 2.31-1: 1V. The locations of the modified re-grade slope are presented <br />in the attached drawing, and represents less than 300 feet of the entire PSSA length. <br />Please note that the re-grade modification does not have any material affect on the PSSA storage or the <br />stability of the VLF. Let me know if you have any questions or concerns. <br />Sincerely, <br />AMEC Earth & Environmental, Inc. <br /> <br />John F. Lupo, Ph.D., P.E. <br />Principal Engineer <br />JFL:jfl <br />AUEC Earth & Environmental, Inc. <br />304 Inverness Way South, Suite 490 <br />Ena3leerood, Colorado 80112 <br />Tel: (303) 433-0262 <br />Fax: (303) 433-0362 <br />kvww.amec.com