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~. ~ . w ~ • of the final product; therefore we are not certain of any particular size that will be processed at any given time. Size as well as quantity of riprap will determine the size and pattern of any particular blast. Due to the nature of this type of rock, small blasts will be conducted to determine the drill pattern and the loading pattern that will produce the desved product. We expect that the underlying rock will produce the highest quality (hardness and wearability) for specific projects such as those for the Bureau of Reclamation, while the outside or exposed portions will produce a less quality product acceptable to private consumers, city and county customers. This is not to say we are unwilling to provide you with blasting information. We have attached some valuable information that should satisfy your request. We have made calculations based nnan a worse The smallest product will utilize the hi est powder factor and the most vibration._ Larger products promo u~at greater stances will be less nbration. This information is contained in the attached Trout Creek QuarTY -Blasting Information". //i2. The reclamation plan for the quarry is as follows. The highwall will be stabilized as the quarry operation progresses by removing any loose material and/or rockbolting if it is deemed necessary, but is not anticipated. Due to the extremely hard nature of the granite in this area, we do not foresee the need for bolting mesh or fencing to the face or the use of shotcrete. These stabilizing methods are available to us, but we are certain they will not be necessary, as is confirmed in the stability analysis. The existing rock outcrops in this area have many vertical faces, and some negative slopes forming overhangs. The attached geologic report for the dam will show that this is very old, stable material. We hope to only have to scale the loose material, thus leaving a more natural appearance. Once mining is completed, the highwall will be left to take on the appearance of the surrounding rock outcrops by natural weathering. The floor of the quarry will be left slightly below the existing grade of the alluvium and covered with some of the recovered alluvial deposit near the Trout Creek channel, transitioning to topsoil and native seeding towards the highwall to leave it with a natural appearance. 7/13. The maps for Exhibit C have been modified to include all of the area within the existing permit area. The legal description, Exhibit A has also been revised to include this area. /j14. Please refer to Exhibit F, Reclamation Plan, where we have indicated the final land use for the ~ different areas. /I5. Since the flood in 1926, Trout Creek has been channeled in various areas as can be seen from the t7 remains of several old channels. Since there are no USGS topo maps prior to 1926, it is impossible to tell where the original seek flowed or where it disappeared into the ground. We have seen no evidence that it flowed into the Arkansas River on the surface. There is curt I a desi ed channel from the stilling basin at the base of the dam. Please refer to the etter Gom Spann Engineering (see Item 16) for a channel data. The channel is based upon the 50-year flood, so it will be more than adequate for the 10-year, 24-hour event any years ago a channel was made to.divert.any_flows.to ),~ ~ ' the south, ou_[ of the permit area, along the base of the rock outcrop that continues to the south for 6~~('~ ~~h H ! ` ` `f many miles. We assume that previous owners of the.agriculturel land to the south may have done this -~ to provide another source of water for crops or livestock. We intend to maintain this channel and we ~'^ 2/~ make necessary improvements to handle a 10-year 24-hour flood event. It is also important to note at these flows are intermittent at best During the initial construction of the RCC dam, the foundation was excavated to bare bedrock where the initial concrete placements were begun. This essentially cut off any ground water flows in the Trout Creek bed. The only Flows in the channel will be when the irri anon line is not in use. If, during any flows from the sway, seepage-from the.. _ rversion channel should show up in the mining areas,__e_d'itch will be lined or sealed to prevent i[. It is for ese reasons that we do not expect to enccunter ground water in the mining areas. Any access across the channel will be made by installing culvert piping, as is the current situation. y'~c-sue r~~ I6. Information regarding the range of Flows in Trout Creek can be found in the attached Hydrology R i r' Report for Trout Creek Dam by Spann Engineering, LLC. Mr. Spann has also included the ~ ~ information fora 10-year, 24-hour storm event in a separate attachment. ` 17. The sand extraction in Area B is not expected to intercept ground water. During the construMion of the RCC dam, the creek channel was removed to solid bedrock where the concrete and RCC were started. This essentially cut of any ground water flows. The only ground water that could be present would be seepage Gom flows in the channel downstream of the dam. The flows in the channel will be intermittent and can be controlled so that seepage will not be a faMOr.