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iii uiiiiiiiiiii iii <br />999 <br />` .t~cmh~f ~n~ ~ss~ri~f~s <br />CONSULTING GEOTECHNICAL ENGINEERS AND MATERIAL TESTING <br />Bowie Resources <br />P.O. Box 483 <br />Paonia, Colorado 81428 <br />Attention: Mr. William Bear, Jr. <br />Subject: Density Test Results for <br />The Bowie Number 2 Mine <br />Waste (GOB) pile East of <br />Paonia, Colorado. <br />Mr. Hear: <br />June 22, 1999 <br />gECEIVED <br />PN: M950~~2GE 1999 <br />ivisicn o. ~~linerala ~ Geology <br />This letter presents comments regarding the density tests <br />performed for the GOB pile which were presented in our letter dated <br />February 24, 1999. <br />Our review of the density tests results which were determined for <br />samples obtained from three (3) test borings located in the <br />existing GOB pile indicates that three (3) samples of twenty-three <br />(23) samples tested had a tested density less than the required <br />ninety (90) percent of the maximum dry density as defined by ASTM <br />D698. All three (3) samples were obtained from test boring 3 which <br />was located about mid slope of the existing GOB pile face. <br />The first sample was obtained from the test boring at a depth of <br />about four (4) to five and one-half (5-1/2) feet with a calculated <br />relative compaction of about eighty (80) percent. The sample <br />obtained from the test boring immediately above the questioned <br />sample had a calculated relative compaction of ninety-three (93) <br />percent. The sample immediately below the questioned sample had a <br />calculated relative compaction of ninety-one (91) percent. <br />It is our opinion that, generally, it would be very difficult for <br />compaction equipment to obtain relative compaction levels of about <br />ninety-three (93) percent for material which is supported on <br />material with a relative compaction of about eighty (80) percent <br />without increasing the relative compaction of the lower layer to <br />provide adequate support for compaction of the overlying more <br />compacted material. <br />Comparison the sample obtained from the same relative elevation <br />from the other test borings indicates a relative compaction much <br />greater than ninety (90) percent. We understand that the GOB <br />P. O. BOX ]986 p. O. 80X 0615 11 < B000 DR. <br />GRAND JUNCTION, CO 61504 µONTROSE. CO 1100] pURANGO. CO E7001 <br />(9]0) 105fi $OE (p70) 309.1150 19]011595095 <br />