2018-05-30_REVISION - M1983035 (3)

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the reclamation of the rest of the operation as fill and plant growth medium is not available on site without stripping it from the undisturbed east end of the permit. But that would be counter productive - why disturb one area to acquire fill when that new disturbance must also be reclaimed? Currently there is a deep basin along the main part of the land south of the area that was mined. The basin was created in the course of mining, but the original reclamation plan appears to call for this area to be fairly consistent with the elevation of the land to the south. The remaining topography to the south of the berm forming the south side of the basin appears to have been somewhat lower than the original surface at the south boundary. No evidence in the permit was found that shows this was the case, so this is a supposition. At any rate,the plan was developed back when it was thought the land to the south would remain range or pasture and very large flows from the reclaimed mined area would easily be controlled by the land to the south and potentially be of some benefit. Now,that is no longer the case. Now, such a flow could damage a great deal of property in the housing development. And it appears that in the creation of the development to the south, drainage was perhaps based on an assumption that the drainage barrier of the berm along the south permit boundary would remain in place. Therefore, completely filling the basin and allowing water to flow southward would likely be very unwise. The current basin along the south side is quite deep and would hold a great deal of water with little hazard of overflowing or breaching the slope that descends into the basin. the south slope that forms the barrier and the southern wall of the basin has a mean slope of about 2.8:1. This grade is quite adequate, except the slope is not uniformly at that grade. From the crest at the top to about 33'down the slope on the north side and 23'on the south side of that berm has a slope of about 2:1 on the north side and about 1.7:1 on the south side, according to measurements. Furthermore,there appears to be a seep zone where rich moss growth was found on the north facing slope about 25 lineal feet below the crest of the slope. Calculating the vertical depth of that zone shows it is about 11 vertical feet below the top of the berm. This also corresponds to a prominent break in the slope on the south side of the berm crest. In addition,this material is much softer and more porous than the material further down the slope where the average slope is about 3:1 or even less steep. It appears that there must be a more firm and less porous surface about 10'to 12'below the crest of the berm. There are no signs of bulging or slumping anywhere on the slope so indications of instability are not present. The berm has been there for a very long time (33 years)and very little erosion has occurred. Therefore,the plan will call for reduction in the height of the berm through removal of about 3' of the cap, primarily to produce a more gradual grade on the south side of the berm. Vollmer Pit Technical Revision June 2018 Updated Reclamation Plan Page 2 of 26