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3.0 DESIGN PARAMETERS <br />Parameters for design were determined based on requirements set forth by Bowie Resources, <br />Limited, and requirements within the Regulations of the Colorado Division of Reclamation <br />Mining & Safety, specifically Rule 4.10 and references therein. The following lists important <br />aspects of the proposed coal mine waste bank design at the Bowie No. 2 Mine, and the <br />parameters that were used as constraints. <br />A large portion of the following design pertaining to the Probable Hydrologic <br />Consequences Sections, Diversion Ditch Design, Sediment pond, etc. located in <br />sections 4.1.4 through 4.3 have been revised with the design and construction of Gob <br />Pile # 4, and specifics can be found in Volumes III & IX. With the approval of TR -44, the <br />Operator began placing waste in Gob Pile #4 which is located to the North of Gob Pile <br />#1. At the time of this writing, Gob Pile #4 has spilled over into Gob Pile #1 and has <br />`absorbed' a portion of the pile. There is only a small portion of the original Gob Pile #1 <br />remaining, approximately 1.1 acres, totaling 32,500 CY of waste material. The diversion <br />ditches associated with Gob Pile #1 have been redesigned and are now located in <br />Volume III. The `gob pond' sediment pond has been renamed `Pond D' and is also now <br />located in Volume III. <br />A revised stability analyses evaluating the steeper slope angle on the western edge of <br />the gob pile is located in Geotechnical Reports Tab of Volume IX. The purpose of this <br />stability analysis is to substantiate a variance request to the approved slope angle <br />construction. The variance request is to allow a 0.1 acre section of the gob pile to be <br />constructed at a slope angle of 1.5H:1V. The remaining area of the gob pile would be <br />constructed at the approved design angle of 2H:1V. <br />Type Coal mine waste bank <br />Capacity 32,500 CY <br />As designed, original pile had a capacity of up to 140,000 CY, but <br />was truncated when it was `absorbed' into Gob Pile #4. <br />Slopes In general, no steeper than 2 horizontal to 1 vertical (2:1) , (Rule <br />4.10.4(4)), static safety factor of 1.5 (Rule 4.10.4(2)). A small <br />section, 0.1 acres, on the western edge is constructed at 1.5H:1 V. <br />Compaction 90 percent of the maximum dry density in accordance with <br />American Association of State Highway and Transportation Officials <br />(AASHTO) T99-74 (or ASTM D-698) in 24 -inch maximum thickness <br />lifts (Rule 4.10.4(3)) <br />Haul Road 10 percent maximum overall grade (Rule 4.03.1(3)), 20 -foot wide <br />minimum width, safety berm, stormwater ditch <br />Diversion Ditches Upland runoff areas for "D" ditches shown on Map 20, Vol. II <br />TR -97 Page 5 11/14 <br />