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'~ <br />Mechanical Laboratory Testing and Results <br />The surface sample of the leach pad granite was tested for durability using the LA Abrasion and <br />the Slake Durability procedures. The laboratory test results indicated that [he loss of material <br />during the LA Abrasion test was 47.7 percent. Given the conditions of use in the underdrain <br />and the fact the sample was a surface sample, this material is suitable for use. This value is <br />believed to represent the effects of weathering and deeper samples in most location are <br />anticipated to be even more durable under the underdrain conditions. <br />Slake durability test results indicate that the "retained pieces remained virtually unchanged." <br />The laboratory data sheets generated to report these results are provided as Attachment 6. <br />LA Abrasion tests were also performed on the granitic material removed and placed on the <br />surface during mining in the Ajax Mine. Testing of this material resulted in the loss of 27.8 <br />percent of the material. Because this Ajax granitic material has been subject only to very recent <br />weathering (over the last 10 to 18 years), it should be even more representative of the granite <br />that will be excavated. The laboratory data for the Ajax granite material are provided in <br />Attachment 7. <br />Conclusions <br />The geochemical and mechanical laboratory test results demonstrate that the granite within the <br />footprint of the valley leach facility will be a suitable source for the underdrain beneath the <br />facility. We therefore request approval and agreement that the subject commitment has been <br />fulfilled. <br />We believe this proposal meets the intent of commitment number 36. We are in the process of <br />blasting and excavating this granitic material. In order to allow us to proceed as smoothly as <br />possible, it would be helpful to have the Office of Mined Land Reclamation's approval within <br />the next few days. To facilitate our implementation, please consider whether your action on this <br />request could be sent by facsimile to us at Cripple Creek. <br />Thank you for your continuing hard work and assistance. <br />Y~ <br />Environmental Affairs <br />(Seven Attachments listed on next page) <br />3 <br />