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The lowest chord of the conveyor bridge will be at least three feet above the effective base flood elevation (BFE, 100 year water surface elevation) as required by UD&FCD through Adams County. The bridge approach ramps will come down from the bridge at 2% to 5% grades on each side of the river. Temporary overburden and topsoil stockpiles will be placed parallel to the overbank flow direction of the River UD&FCD comments and will have a maximum height of 20' and base width of 100'. The stockpiles will be limited to 300' in length, with minimum 100' gaps between, to avoid levee type floodplain constrictions. Agreement with UD&FCD will be necessary on river stabilization improvements required to mine within 400' of the river banks. Other activities within the regulatory floodplain, such as emergency overflow areas at reasonable intervals in the reservoir banks, will require UD&FCD approval and local floodplain regulatory approval by Adams County by issuance of a Floodplain Use Permit. The Floodplain Use Permit application will include a hydraulic analysis of the S. Platte River to evaluate the proposed floodplain features created in the mining. The preliminary findings of the hydraulic analysis indicates no rise in the floodplain effective BFE's due to the conveyor bridge, bridge approaches, and overburden stockpiles, which is in conformance with Adams County requirements. Surface Water The mining operation is adjacent to the Fulton Ditch as shown on Exhibit C-l, Pre-Mining Map, Exhibit C-2, Mining Plan Map, and Exhibit F, Reclamation Plan Map. The proposed mining operation will setback a minimum of 50' from the edge of the outside ditch bank. The perimeter of the ditch will Ge adjacent to active mining for approximately 2,800'. The Fulton Ditch will not be disturbed during the mining and reclamation operations. However, the groundwater lake elevation will not be different from historic levels because no dewatering is proposed. The Spring Creek Seep Ditch from the Bull Seep feeds into the Fulton Ditch just downstream of the head gate. Although there is no specific water rights attached to this seep, it is recognized as a source of supply to the Fulton Ditch. The length of the seep ditch passing through the permit area is 1,300 linear feet. There will be no mining in the area of the seep and it is not expected to be adversely impacted by the operation. There are some minor ditch laterals on the CAMAS property to the west of the river that will be relocated during the mining process. There are no water rights associated with these laterals and appear to only serve for returning tail water to the river from adjacent irrigated fields. The ditches will be rerouted around the mining area to maintain drainage across the property. 2