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_ - Exhibit D - Mining Plan 1. Please specify whether the aggregate will be processed on-site. Processing includes crushing, screening, washing, concrete or asphalt mixing. If the deposit will be processed, then describe the nature of the processing, facilities and chemicals utilized. The description should describe the measures to be taken to minimize disturbance to the hydrologic balance, prevent off-site damage, and provide for a stable configuration of the reclaimed area consistent with the proposed future land use. 2. You plan to isolate your working areas from the main river flow by using dikes and berms. Also, you plan to have your haul roads located away from the main river's flow. It seems that it will be necessay to confine the river's flow into a single channel located away from the mining areas and haul roads, and probably along the eastern side of the channel. Is this true? If so, then the river water will be concentrated along a narrower channel than would naturally occur. That water should tend to be more erosive along the banks of the confined channel and slightly up and downstream as well. Increased erosion along these banks could cause unstable slopes, excessive water sedimentation, and off-site damage. We recommend that you should plan to prevent these consequences by maintaining armoring along the eastern bank of the river along the stretches of confine4 river channel and a sufficient distance up and downstream. Please commit to this. 3. You have stated that mining excavations will not extend below the water level of the river, and that the streambed will not be excavated below the low water level of the river. Please define "low water level", what elevation is this, and how will your equipment operators know how deep they can dig? We recommend that the average low water level should be determined from historical data, and that level should be the elevation below which material should not be removed. We recommend that operations never occur below the river or ground water level, even if the river is above the low water level. Equipment operators should be informed that they may excavate to either above the water level or until the low water level elevation is reached, whichever occurs first. We recommend that the low water level elevation is surveyed and posted for easy field reference. Finally, you should determine approximately how much fluctuations occur in river and ground water levels on a daily and weekly basis, so that excavation depths can be maintained above the expected water levels during active operations. 4. Both Sandco, Inc. and the Division are procesing this appliation with the mutual goal of allowing maximum mining extractions while minimizing adverse effects to the Animas River system. With the knowledge that we have at hand, I believe that this operation can accomplish those goals. However, you and other local gravel producers, local citizens, La Plata County, and the Division agree that the impacts of gravel extractions along the river are not well understood, An Animas River Management Plan and study has been initiated to document and manage these impacts. Your La Plata County special use permit requires you to participate in this study. Recommendations in that plan and study are to be incorporated into your operations, according to your County permit.