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Spoil Fill N9 <br />September 30, 2006 <br />Page 2 <br />FILL PLACEMENT <br />CDMG regulations require that spoil be "placed in horizontal lifts in a controlled manner, concurrently <br />compacted as necessary to ensure mass stability". Maximum lift thicknesses are not specified. As indicated <br />by previous inspection reports, lifts were placed in accordance with plans specified by the CTL Thompson <br />report Spoil material was transported to the fill area using a combination of trucks and dozers. Lift <br />thicknesses of up to 50 feet were placed within the area removed from the 511 face by more than 50 feet. <br />Fill placement terminated by second quarter 2002. <br />No fill placement occurred during this quarter, nor is fudne placement anticipated. <br />COVER MATERIAL <br />As documented by previous inspection reports, cover placement, seeding and mulching was completed <br />during the second quarter 2002 and upper areas during the second quarter of 2004. During the second <br />quarter of 2005, areas disturbed by maintenance of the armored down-drains were hand seeded using <br />certified weed free straw and the approved rangeland seed mix. <br />STRUC[JRAL INTEGRITY <br />The entire excess spoil fill facility was examined for signs of failure and instability such as tension cracks, <br />ground movement, springs and seeps, and standing water. No indication of potential instability was <br />observed. <br />DOCUMENTATION AND OTHER OBSERVATIONS <br />Rain events typically occurred two or more times per week yield'mg 0.25-0.6.0 inches per event, but were of <br />reduced intensity, allowing the moisture to permeate the soil with only lintited runoff. Total precipitation <br />at Lorencito was 1.3" in July, 3.25° in August, and O.T' in September. No significant erosion was noted <br />with established drninages functioning as designed. <br />This inspection was conducted by Ronald G. Thompson, a qualified professional and MSI-IA certified <br />inspector of earth and rock-fill embanlmrants and impoundments, under the direction of Mr. Charles <br />McGlothlin, a registered professioanl engineer licensed in the State of Colorado. <br />This is to certify, to the best of my lmowledge and belief, that Fill No. 9 construction and placement, as <br />noted since the previous certification and as determined dining this inspection and discussions with mine <br />personnel, is in accordance with desigms as proposed by CTL Thompson in they report dated April 27 and <br />amended July 27, 2001 and as approved by the Division of Minerals amt Geology. <br />~~ <br />Ronald G. Thompson Charles W. McGlothlin ,'_ ~ ~„ <br />Inspector Professional Engineer - -' _ - _ <br />h^q~_ ^ _ .'~.Sr <br />- .,\.. <br />