2004-07-27_REVISION - M1981044 (2)

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Earthmovine Onerations (Soil & Overburden Salva As a new area is opened for gravel extraction the topsoil is pushed aside, typically with a bulldozer. As a result topsoil stockpiling occurs around the perimeter of the mining area. This facilitates the replacement of topsoil over the regarded area by simply using the bulldozer to push the topsoil on to the new slopes. The sandy to gravely soils removed to its full depth as indicated by a color change. The depth of salvage averages about 8", but can be as much as 12" to 14" in some places. The color change usually indicates the point where the upper, more organic material meets the subsoil. Because the soils covering the gravel are poorly developed (see soil information) there is little concern about separating A horizons from B horizons. The B horizon is not usually present in this area. The soils on this site developed from the gravel deposit through biological action and therefore, except for the organic component, the subsoil has little physical differentiation from the upper organic layers. Overburden, in the true sense of the word, is not usually encountered. Essentially the soil is the overburden. Once the soil has been removed, inmost cases, the gravel deposits aze fully exposed and ready for mining. Drainage Control: The mining plan map and the reclamation map, when combined, show the pit will drain in two directions. In the earlier stages the pit will drain toward the intersection of Garrett and Cutts roads as it has done throughout the history of the site to this time. Sediment control is accomplished within the pit. Through the use of gradual slopes in the pit bottom as well as shallow depressions the rate of flow is reduced allowing nearly all sediment to settle out prior to the water leaving the pit. The bottom of the pit will have a very gradual slope (1 % to 2%) over a considerable distance allowing for sediment control while still permitting water to leave the site quickly in order to reduce to potential for ponding. Area Worked at Any One Time: As a result of the intermittent nature of the operation and the relatively low production volume it is difficult to identify a discrete amount of land that is operated at any on time. A particular working face may be exposed for yeazs with change in the actual area operated increasing by only a few thousand square feet. On the other hand, during periods of heavier activity it would not be unusual to see one or two acres of material removed. This however is a rare occurrence. This operation has been in place for approximately 34 years and the total disturbance is only 35 acres. Rather than indicating an area worked at any one time, the disturbance category differentiation is utilized to describe hoe the operation proceeds and how the mining will