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2) Move Excess Sand Pile into Lake Immediately Southwest of the Pile. Since the surface of the current reclaimed area immediately west of the sand pile has risen in elevation approximately 5 feet, it will be assumed that the bottom 3.0 feet of the sandpile will be lek to maintain this constant elevation, since 2.0 feet of topsoil will be added to the sand which is left. Measwements were made with tape, level, stadia rod in November of 1997. Aerial photos from this same time were used in assessing the pile area. This information showed that the pile covers an area of approximately 19.4 acres and has an average height of 20.0 feet. This results in a total volume of 626,000 cubic yards (cy). Assuming that 3.0 feet of the sand will remain, the material to be moved is 17/20 x 626,000 cy or 532,000 cy. The lake immediately southwest of the sand pile is approximately 1050 feet long x 750 feet wide and averages 35 feet deep. This is a volume of 980,000 cy. Therefore the sand pile to be moved (532,000 cy) will not completely fill the southwest lake. Therefore, a partial lake will be left on the western side of the existing lake as shown on Exhibit F-2, which shows the final reclamation of the End 1998 Scenario. The lake west of the sandpile will primarily be left for wildlife habitat. The minor sandpiles between this lake and the lazge sandpile will be used to build shallow shelves for wetland plants as previously described in the reclamation plan section. Using methods outlined in the Caterpillar handbook , it was found that the cheapest conventional method to move the material an average distance of 700 feet at a grade of 0% is to use Cat 637E scrapers . Using a team of 2 scrapers at a unit cost of $195 per hour results in a team cost of $390 per hour. With a site altitude of 3400 feet, the net job correction factor is 0.81. The adjusted haul volume of 26 cy per load x .81 job correction factor = 21.06 cy per load. Using a total cycle time is 2.5 minutes, the following calculations apply: # of trips = 532,000 cy / 21.06 cy per load = 25,261 trips. Time needed = 25,26] trips x 2.5 minutes per trip = 63,152 minutes or 1052 hours. Since 2 scrapers are used, the team time is 1052/2 = 526 hours. The scraper team cost is $390 per hour, therefore the job cost is $390 x 526 hrs = $205,245. A Cat D-8 dozer will also be needed to assist in spreading the material after scraper dumping. Using a cost of $150 per how for 380 hrs results in a dozer cost of $57,000, therefore the total cost to move the material is 262 245 or $0.49 per cubic yard, not including contractor profit. This cost is considerably less than the worst case scenario described previously since the average move distance for the sand has decreased from 2100 feet to 700 feet. 3. Remade Sand Piles behind Lake. Using the same measurement tools described for the large sand pile, the minor piles behind the lake were also estimated in November of 1997. Aerial photographs were also used in showing that these piles have an area of approximately 12.0 acres and an average height of 6.4 feet, resulting in a volume of ]23,904 cy. Since this material can be pushed directly by dozer into the adjacent lake, the estimated cost of completing this work is $0.30 per cy, therefore the total cost for this task is 37 17 i . 4. Retopsoil all areas for Revegetation. As shown in the reclamation table, the area to be retopsoiled is 60.9 acres. At an average 59_2 Pir Qnte,roMEr.rr IzI4S