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TRRRPER MINING INC TEL~303-824-4632 Jan 04 96 1336 No .005 P.09 <br />s <br />The Division also posed the question of shift selection for <br />backfillinq and regrading work. All of the contractors stated that <br />single shifts would be used Por backfillinq if there is no <br />production quota. Not one of the contractors would use triple <br />shifts for the described work. The Division feels that the usage <br />of double shifts is appropriate based on the statements from the <br />contractors. Please note the cost for double shifts vs. the <br />equipment cost Por single shifts on the enclosed cost reports. <br />Job Correction Factors <br />Trapper states that the visibility factor for double shifts should <br />be o.95, representing 12 hours oP day work at 1.00 and 4 hours of <br />night work at 0.80. The Division agrees with Trapper regarding the <br />distribution of day light hours vs. night hours, but the visibility <br />factor also takes into account dust, rain, snow or fog. The factor <br />of 0.95 used by Trapper Inc. does not take these other conditions <br />into account. There will be quite a bit of duet crested by <br />backfillinq and grading that will lower the visibility factor. The <br />weather conditions such as snow, rain snd fog will also decrease <br />the visibility, and the possibility of such weather occurrences is <br />highly probable. The Division's factor of 0.90 takes all these <br />factors into consideration. The Division Peels confident in the <br />0.90 correction factor for double shifts, and recommends that it bo <br />incorporated into the estimate. <br />Trapper feels the job efficiency factor of 0.83 will not change <br />with the addition of shifts. According to the Caterpillar Handbook <br />shifts done at night are based on 40 min/hr. vs. the 50 min/hr. for <br />shifts does in the day light. The Division takes the average of <br />the 4o min/hr. and the 50 min/hr to get the correction factor of <br />0.81. The correction factor for triple shifts is 0.79. The job <br />efficiency is lowered to 0.79 at night due to the 40 min/hr. Based <br />on the information supplied in the Caterpillar Handbook, the <br />Division feels that a correction factor of 0.81 is appropriate for <br />double shifts. <br />Final Grading <br />The Division estimated the cost for final grading of the site using <br />a Caterpillar 16G Motor Grader. The initial estimate done by the <br />Division was based on medium grading at 1.65 acres/hour. The <br />Division re-estimated the final grading using a light'grading <br />method. Light grading adjusted hourly unit production is 3.30 <br />acres/hr. This comes to a total of $70,066.62, roughly half of the <br />original estimate. Please review the attached motor grader form <br />and let me know if you have any questions. <br />Roads <br />Trapper agreed to include a cost for ripping the roads associated <br />with the mine. The Division feels that a seismic velocity of 5000 <br />feet/sec. is an appropriate velocity for road material. With the <br />ripping of the roads, the material consistency factor can be <br />