2008-05-01_REVISION - M1973007SG (5)

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MINING PLAN As the glaciers melted and more vegetation became established on hillsides and slopes, the texture of the alluvial sand deposited declined to smaller sizes, but wind sorting and deposition continued. Thus on top of the more coarse sands, finer sands were deposited. But even high in the deposit seams of very coarse, almost pebbly sand can be found here and there. These probably represent major flood events, the effects of which were preserved by subsequent fine sand deposition. Most of the upper sand in the deposit appears to be much more of an aeolian source with only minor amounts of alluvial sand. At this time, it is likely the landscape was very similar to what is seen today,but periodic droughts allowed huge sandstorms to deposit fine sand across the area. The vegetation was primarily grassland as it would be today without the city,but the pine forests that are the Black Forest of today were probably not far to the north. These forests, now well north of the city, are probably receding northward to the higher, more moist ridges of the Palmer Divide and are probably being replaced by grassland as the climate continues to warm. This historical deposition pattern is supported by the presence of sinuous but discontinuous seams of coarse gravel up to 20 feet thick that underlie the sand deposit. On top of that gravel is a clay layer about 6" to 12" thick. The gravel does not occur everywhere under the sand. The gravel contains the primary aquifer that exists under the sand. In fact, very little water is ever encountered in the sand itself. But the clay seam appears to be quite continuous and forms a separation layer between the upper sands and the lower gravel. It appears that at one time,before the sand was deposited, swift streams flowed through this area and these streams probably came from the mountains where the wide variety of igneous and metamorphic rocks found in these gravels originated. These deep gravel beds may have been the ancestral Fountain Creek. These gravels may date back to much older ice ages or the later periods of uplift in late Miocene or Pliocene times when erosion was intense as a result of the most recent uplift of the Rocky Mountains. More likely, these gravels represent deposits formed during peak melting of the glaciers when it is likely the entire area around Colorado Springs and the Fountain Creek Valley may have been a vast, almost denuded outwash plain covered with deep, rock filled,braided streams that frequently flooded the land. The clay on top of the gravel and below the sand may be glacial flour derived from the bursting of dams holding back glacial lakes and the vast volumes of fine sediment deposited in those lakes during the melting of the glaciers. From that time on, deposition shifted to a more sandy rather than a gravelly form or the gravel deposition shifted to another location leaving this area to receive the 60 to 100 feet of sand that is the deposit mined today. It is possible, water continued to flow over this area,but the flows were more gentle and deposited mostly sand. It is also possible drainage patterns into this area shifted from primarily out of the mountains to primarily off the plains to the east and northeast. In fact, it appears the Little Johnson Reservoir is underlain by an east to west flowing paleochannel that has subsequently been filled with sand and now carries groundwater that descends below the sand deposit in the Daniels Pit. In part, it Daniels Sand Pit Amendment (2008) Exhibit D Page 3 of 28