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~~ <br />Based on the average (recoverable) sand i£ gravel thickness of 39 feet, and a ten percent <br />waste factor, the property should yield approximatety 90,000 tons per mineable acre. The <br />deposit tended to have more day seams along the eastern portions of the property, with the <br />alluvium being ceaner towards the west and with depth. Harder drilling was encountered on <br />all holes as weathered bedrod< was approached, indicating coarser gravels and cobbles, <br />although only smaller aggregate sizes were observed in the auger cuttings bequse of the <br />auger size. <br />Since the existing oil wells, underground pipelines and irrigation ditch bisecting the property <br />would greatly influence the ability to effectively mine the property, and potentially the water <br />storage capacity of the property, the reserve estimate was analyzed two ways. Both <br />approaches assume the existing farm structures will be removed for mining. Relocating the <br />two pipelines north of these buildings may not be cost effective; some of this area could be <br />backfilled with overburden to recreate a building site with road-frontage. <br />First, the areas which could be reasonably mined without relocation of any utilities were <br />plotted on the first map of the property, assuming typical set-backs and mining limits. This <br />approach yielded five separate mining areas, 53.2 mineable acres, and approximately <br />4,800,000 net tons. <br />The second approach involved relocating the diagonal pipeline along the west and north <br />property lines and relocating the inigation d'rtdt to a combined corridor (after the area had <br />been mined and backfilled to grade with overburden materials). This increases gravel <br />recovery, reduces the slope backfill requirements, and increases water storage. This ~z eM 5 <br />approach yielded three.separate mining acres, 54.6 mineable acres, and approximately le/ <br />4,900,000 net tons. The cost of relogting the 1700 LF gasline with 2300' along the property <br />lines was $46,000. The pipeline was conservatively placed 25' from the property line; getting <br />doses would increase the gravel recovery and water storage values. Relocation of gaslines <br />increases in gravel recovery slightly, but the main advantages are increased water storage <br />and decreased earthwork. <br />Net water storage was roughly estimated (without considering elevation changes across the <br />property) as 1145 AF for the first scenario and 1460 AF for the relocated scenario. This <br />assumed a freeboard requirement of 3 feet, an average pit depth of 47 feet, and 3:1 slopes. <br />The reduced perimeter of mined areas requiring slope backfill resulted in 360,000 CY <br />reduction (1.93M-CY vs 1.53M-CY, and 40,000CY to badkfill the ditch alignment to grade. <br />This backfill reduction is important, since the site will yield about 600,000 CY of overburden, <br />with the balance of baddill excavated from tfie pit floor. Although not drawn, relocating the <br />two southern gaslines would save about 300,000 CY of fitl, add up to two acres of mining, <br />and increase water storage another 270 AF. <br />In conclusion, there are approximately five million tons of useable sand and gravel, with the <br />potential of 1700 AF of water storage capacity. <br />• Page 2 <br />