2004-07-27_REVISION - M1981044 (2)

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The minor disturbance category is land awaiting completion of revegitation development. The amount of land included here assumes revegitation will take five years. Therefore when the acreage limitation is reached in this category the only way to reduce the actual land in the category is to get is released from bond. If it takes longer than five years to revegitate the land and the limitation has been reached, then the only alternative is to provide more bond and increase the amount of land in this category. The amount of land in each category will be monitored periodically and will be reported in the annual report. Thus both the permittee and the Division can be assured the limitations are not being exceeded. In the event the acreage limitations need to be exceeded then the limitations will be increased and addition bond provided through the technical revision process. Timetable: Phasine: The operation does not have a discrete phasing arrangement because of the use of disturbance categories to define the limits to the area that can be worked at any on time. Essentially, the pit is operated on a continuous basis within the defined limits. Directional Trend: In the past the operation worked from east to west along the northern ridge of the gravel. Through a drilling program the current configuration has been defined. At present the operation has turned and begun a north to south operation. This direction will continue down the ridge until the operation daylights at the drainage to the south. Nature, Depth, and Thickness of Gravel Deposit: The gravels in this area tend to be extremely spotty and exhibit configurations that indicate old stream channels and deposition on an old erosion surface. The material itself tends to be extremely variable over even short distances. The valleys in the current topography tend to be associated with more sandy material while the ridges often represent gravel seams. However, this pattern is not always consistent and occasionally sand is found on hill tops and gravel in the valley bottoms. The material to be mined on this site ranges in thickness from a few feet to many tens of feet. Well logs in this area show occasional pockets of sand and gravel layering that can be well over 100 feet thick. In general, the depth of mining on this site will be restricted to about a maximum of 40 to 50 feet with an average of 30 feet. Interspersed with the gravel and sand layers aze clay seams that can be a foot or more thick. These apparently represent altered during depositional stages of the erosion cycle that produced the deposits. These clay seems are important to the overall quality of the material on this site. The El Paso County Road Department, the primary customer using this material, needs the clay in the sand and gravel blend to provide a binder when the material is applied to the roads.