2008-05-01_REVISION - M1973007SG (5)

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MINING PLAN maintain the sand production so long as finished slopes are not affected by the mining. Once this is completed reclamation of the remaining unreclaimed land can begin. Sequencing of Mining: For the most part,(no specisequence will be observe in the mining of the sand in the North Area. Clearly though, lands influenced by the adjacent highway as well as the ditch relocation dictate some sequencing. Sequencing is primarily a matter of mining different grades of sand so the wide variety of sand products created can be maintained. Unfortunately, the sand deposit itself exhibits considerable variability in texture. It is essentially all sand, but the sand that is present varies from very fine sand to a coarse sand that contains almost small pebble sizes. During the processing of the sand, these different sizes are separated to produce the variety of products. Therefore, having a continuous supply of variable particle sizes is necessary to maintain the product stream. In general, the finer sands are near the top of the deposit and the more coarse sands are deeper in the deposit. But this is only a general pattern. Fine sand can be found deep in the deposit and coarse sand can occur in the upper portions of the deposit. Because this sand is a combination of stream deposited (alluvial) sand and wind blown(aeolian) sand, considerable variation can be expected at any one level in the deposit. Furthermore, at even the same level in the deposit, sand that was deposited by a meandering stream may be more coarse. But during low water flow periods, some of the finer sand deposited by the stream may have blown on to adjacent very slightly higher sand bars next to the stream thereby producing a finer textured sand where the wind blown sand was deposited and leaving a coarser textured sand where the stream flowed. Whether this sorting is maintained into the final deposit or not depends on whether the sorted fine and coarse sand are re- mixed by subsequent stream flow, erosion, and channel shifting or whether it is buried by more sediment and thereby preserved in the final deposit excavated today. Furthermore, additional alluvial sorting may occur if a brief erosion cycle removed previously sorted materials and deposits it elsewhere within the area to be mined or somewhere else, followed by deposition of new material that may establish a whole new array of particle sizes. The point is, predicting exactly what kind of sand will be at any particular location would require knowing the complete, almost daily history of the formation of the entire deposit over a period of tens of thousands or even a few hundred thousand years. That, of course, is impossible. The next best thing is to simply be flexible in the mining of the deposit so the full array of sand types and textures are available. Certainly, the highway slope must be created along with the ditch route and the timing of completion of each of these is largely dependent upon the schedule for construction of the highway. It is important to have the highway slope and at least the west to east leg of the ditch corridor completed by the time the highway is open for traffic. It would not be wise to have mining occurring near the highway as blowing sand could be a problem as well as just the visual impact of having a Daniels Sand Pit Amendment (2008) Exhibit D Page 25 of 28