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requires 'overburden to be blasted immediately over exposed coal in the truck/shovel operation. Therefore, this practice often requires that the coal be cleaned twice, which is costly, and decreases coal recovery. This problem can be eliminated by widening the pit approximately 75 feet. 3. Colowyo has very limited in pit reserves, which are necessary to reduce the risk of lost coal production due to equipment failures. Original mine plans provided in pit reserves by pre-stripping the X level coal approximately 300 feet, thus providing 600,000 tons of in pit reserves (approximately 1.5 months at the projected production of 4.5 million tons/year MTPY.) These reserves are required even now. 4. Colowyo's original design also planned for a rehandle dragline. A study is currently being conducted utilizing actual operating conditions to determine the feasibility of a rehandle dragline operation. If this study proves positive, the pit will need to be expanded an additional 300 feet in width to provide sufficient operating room for the rehandle dragline. 5. Currently, coal sales are increasing and Colowyo may be able to increase from 3.0 to 4.5 MTPY somewhat faster than anticipated. To do this, the additional truck/shovel operation will be started early, creating a need for extra truck/shovel overburden fill space. The fill space requirements for these improvements are as follows: 1. Immediate shortage 3.0 Million (M) BCY 2. Additional 150' for flexibility and safety 3.7 MBCY 3. Additional 75' for blasting operations 1.8 MBCY 4. In pit reserves 5.1 MBCY 5. Requirement for rehandle dragline 6.0 MBCY 6. Acceleration of coal sales 6.8 HCY, Total X26.4 MBCY~ Expansion of Streeter Fill The proposed expansion of Streeter Fill as shown on Maps 1 and 2 will provide sufficient additional volume to allow all of the above improve- ments to be implemented at the Colowyo mine. The permit boundary will be increased by 134.62 acres, a 2.6 percent increase of the current permit area of 5104.39 acres. However, the disturbed area will only be increased by approximately 45 acres. Colowyo has requested Tipton and Ralmbach Inc., Denvec, Colorado, to review the previous stability studies that have been conducted on the Streeter Fill and provide an opinion of the effect that the proposed expansion would have on stability. Their opinion is provided in the attached May 5, 1981 letter. The first phase of all construction will begin near the northeast edge of the Streeter Fill and will move in a north and west direction (see Map 3). The second phase of construction will begin from the west after