GENERAL39315

• Permit No: M1994117
• IBM Index Class Name: General Documents
• Doc Date: 10/10/1995
• Doc Name: REQUIREMENT TO REMOVE HAZEL-A SLIMES-GOLD HILL MILL-PN M-94-117
• From: DMG
• To: COLINO ORO MOLINO INC
• Media Type: D
• Archive: No

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DIVISION OF MINERALS AND GEOLOGY ggg
Department of Natural Resources ~~~~~
1313 Sherman 51., Room 215
Denver, Colorado 80203
Phone: [phone]
FAX: [phone]
DEPARTMENT OF
NATURAL
RESOURCES
October 10, 1995 Roy Romer
Governor
Ms. Gwen Fraser lames S. LOChhead
Execmive Director
Colina Oro Molino, Inc.
Michael B. Long
3801 West Marginal Way, SW Division Duec log
Seattle, WA 98106
Re: Requirement to Remove Hazel-A Slimes, Gold Hill Mill,
Permit No. M-94-117

Dear Ms. Fraser:
The Division has completed an analysis of the fine grained earthen
material deposited on the sill of the Hazel-A adit behind the water
impounding bulkhead. The Division collected a sample of this material
during a site inspection conducted on August 26, 1995. Tim Hartley and
Ric Fanyo, representing Colina Oro Molino (COM), Inc. were present during
the inspection, and were provided a split of the sample collected. The
Division contracted with ACTLab of Denver to prepare polished thin
sections of the fine grained material.
The thin sections were examined by myself and Harry Posey, PhD, Division
staff geochemist, at the United States Geological Survey microscopy lab
at the Denver Federal Center on October 4, 1995. Dr. Posey has extensive
experience in ore microscopy and microscopic examination of mill tailing.
As a result of our analysis, the Division has determined that the material
deposited in the Hazel-A adit is tailing slimes from the Gold Hill Mill.
The bases for this determination are:
1. Angular, and occasionally cracked mineral grains, of predominantly
similar size. Grains exhibiting very large length to width ratios.
Reentrant angles along the edges of individual grains. It is the
Division's view that the shapes of the individual grains would not
be consistent with formation by geological processes, but would be
consistent with grinding in a mill.
2. A lack of clay minerals that should be
materials that were a product of geologic
3. Presence of at least four phases of
indicative of a mineralized source for
consistent with a mill tailing source.
The Gold Hill Mill Reclamation Permit requires
present in fine grained
processes.
sulphide mineralization,
the Hazel-A slimes, and
that all mill tailing be