1999-02-05_GENERAL DOCUMENTS - M1977493 (7)

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• • Conveyor demolition is somewhat more complicated than cribbing removal. DMG's method, as outlined in Sorenson's April 27, 1997 memo is a logical and reasonable approach. However, DMG's procedure of doubling the cost per lineal foot for an elevated conveyor is excessive, based on experience at other Cyprus sites. Steve Thomas of Wayne Gomez Demolition and Excavating (personal communication, 11- 11 -97) was consulted about demolition of elevated conveyors. It was Thomas' opinion that an elevated conveyor would have its supports shear -cut and "dropped" in place to facilitate the removal of the components and the salvageable steel. His estimate was that it would increase the cost by a factor of 1.25 (25% more). In an effort to confirm this figure, Jeff Mueller at Ayrshire Mine in Indiana (personal communication 11- 11 -97) was consulted because Cyprus Amax Coal had recently completed tearing down a large coal preparation plant (summer of 1997). The Ayrshire prep plant conveyor demolition (300 -350 feet) was accomplished at basically no cost, because the belts, rollers, idlers, etc. were salvaged, thereby off - setting the cost of demolition. Nevertheless, Jeff Mueller confirmed that observing the demolition of the elevated portions of the conveyor indicated to him that it was definitely not twice as costly to demolish an elevated section. This observation by Mueller was interpreted as an affirmation of the 25% increase in demolition cost to remove an elevated conveyor. Presented on the a conveyor back -up worksheet (tabbed "conveyors" in the "demo- costs- M493- 5- 11- 11 -97" workbook) are three methods labeled "Climax Method No.1, DMG's Method, and Climax Method No. 2." A brief discussion of each method follows. Climax Method No. 1: Using the standard demolition cost of $0.13 / cu ft (as used throughout the worksheets), demolition costs were computed for each conveyor on grade. For the elevated conveyors, cost of $0.163 ($0.13 + 25 %) was utilized. This seems like a reasonable approach, since there is nothing unusual about conveyors, except they probably have a very high salvage value which this study ignores. Total conveyor demolition cost was calculated as $223,693 by this method. DMG's Method: Using the on -grade cost and doubling it for elevated sections, DMG has estimated costs on a lineal foot basis. The DMG costs are over - estimated by the doubling factor for reasons clarified in the discussion above. Again, this method totally ignores salvage value, which could easily offset the demolition cost. Total conveyor demolition cost was calculated as $516,309 by this method. Climax Method No. 2: This method accepts the DMG approach except that the costs for removal of elevated sections are only increased by a factor of 1.25 instead of by a factor of 2, for the reasons mentioned above. Again, no salvage value was assumed. Total conveyor demolition cost was calculated as $301,569 by this method. For purposes of incorporating a "logical and reasonable" conveyor demolition cost into the overall Excel Worksheet ( "demo- costs- M493- 5- 11- 11 -97 "), the Climax Method No. 2 was selected, as it represents a "middle- ground" estimate between the other two methods.