2012-09-05_REVISION - M1995030 - Laserfiche WebLink

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MINING PLAN EXHIBIT D (cont) Within this area is the existing 110 permit area. Mining started on the west end and is progressing to the east as mate- rial is mined. A portion of the eastern end of the existing permit area has been stripped for growth medium by the previous owners. The existing permit area contains a 2.76 acr lake, a 1.52 acre partially stripped area and growth medium s ockpiles containing approximately 2500 yards of material. The site is bisected by the Edwards -Gill Drainag0 ditch that was listed on the abandonment list in 2000. We can find no ownership listing for this ditch and it appears to carry seepage water from up gradient properties. It enters the property in the southwest corner and flows north along the west line for approxi- mately 520 feet. It then turn east and crosses the site exiting 530 feet north of the southeast corner of the east line. This water feature is shown on all maps. GEOLOGIC SETTING The affected lands are located along the South Platte River in a Quaternary age, Piney Creek alluvial deposit. The eastward dipping beds of Upper Cretaceous age are overlain at an angular unconformity by the Pine Creek alluvium. The sand and gravel encountered in the Piney Creek alluvium are a result of water erosion and redeposition of rock materials from the front range of the Rocky Mountains. The deposition of this material occurred during a time when the river was much larger that it is now. But, judging from the scarcity of large rocks found at the location, the velocity of the river must have slowed sufficiently to have dropped boulders and most large cobble before it reached this point. This type material is found from south of Denver to the state line along the South Platte River. The quantity of course gravels and sand vary from a ratio of 80% rock to 20% sand in Denver to 30% rock 70% sand at Julesburge. We have found along this section of the river has a 20% rock, 80% sand and the deposit is approximately 60 feet deep. As you move to the south across the property the deposit appears to be uniform in depth. Overlying the deposit is a thin layer of soil that varies from 0 to 17 inches averaging 6 inches overall. This is not soil in the general sense of the word, as it lies in the South Platte River flood plain. Having been flooded numerous times over the years the surface soil is sandy in nature and contains little loam or humus that would make it a good topsoil. For sake of discussion, we will refer to the upper 8 inches of this soil as growth medium so there is no misunderstanding as to it quality. Underlaying 6