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DIVISION OF MINERALS AND GEOLOGY <br />Department of Natural Resources <br />1311 Sherman 51., Roam 21 5 <br />Denver, Colorado 80203 <br />Phone' (303) 8663567 <br />FAX: 13031 832-8106 <br />October 10, 1995 <br />Ms. Gwen Fraser <br />Colina Oro Molino, Inc. <br />3801 West t+iarginal Way, SW <br />Seattle, WA 98106 <br />GTAT~' OF' <br />~~~ ~I~~I~~~~~~~~ ~~~ <br />999 <br />Re: Requirement to Remove Hazel-A Slimes, Gold Hill Mill, <br />Permit No. M-94-117 <br />Dear Ms. Fraser: <br />~~ <br />DEPARTMENT OF <br />NATURAL <br />RESOURCES <br />Ruc Numer <br />Goreuvu <br />lames $. Loc hhead <br />EKPCUIice DireClor <br />mu ha el 6. LwrX <br />Dn'~smn Diwanr <br />The Division has completed an analysis of the fine grained earthen <br />material deposited on the sill of the Hazel-A adit behind the water <br />impounding bulkhead. The Division collected a sample of this material <br />during a site inspection conducted on August 26, 1995. Tim Hartley and <br />Ric Fanyo, representing Colina Oro Molino (COM), Inc. were present during <br />the inspection, and were provided a split of the sample collected. The <br />Division contracted with ACTLab of Denver to prepare polished thin <br />sections of the fine grained material. <br />The thin sections were examined by myself and Harry Posey, PhD, Division <br />staff geochemist, at the United States Geological Survey microscopy lab <br />at the Denver Federal Center on October 4, 1995. Dr. Posey has extensive <br />experience in ore microscopy and microscopic examination of mill tailing. <br />As a result of our analysis, the Division has determined that the material <br />deposited in the Hazel-A adit is tailing slimes from the Gold Hill Mill. <br />The bases for this determination are: <br />1. Angular, and occasionally cracked mineral grains, of predominantly <br />similar size. Grains exhibiting very large length to width ratios. <br />Reentrant angles along the edges of individual grains. It is the <br />Division's view that the shapes of the individual grains would not <br />be consistent with formation by geological processes, but would be <br />consistent with grinding in a mill. <br />2. A lack of clay minerals that should be present in fine grained <br />materials that were a product of geologic processes. <br />3. Presence of at least four phases of sulphide mineralization, <br />indicative of a mineralized source for the Hazel-A slimes, and <br />consistent with a mill tailing source. <br />The Gold Hill Mill Reclamation Permit requires that all mill tailing be <br />COLORADO <br />