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wet because most of them will be removed from under water. Time will need to be provided in a construction schedule to dry the materials to a moisture content acceptable for compacting into the embankment. Bridges. Three bridge sites were looked at. One of the sites is across Deer Creek and the other two are across the South Platte River. One of the sites across the South Platte River is the site of an existing bridge. We observed no geologic or geotechnical reasons the construction or reconstructions of bridges at these sites are not feasible. The ground under the abutments of the Deer Creek site is different. Our observations suggest the foundation strata for the east or left (looking downstream) abutment of the Deer Creek Bridge is expansive clay overlying expansive claystone. Our observations suggest the foundation strata for the right abutment is several feet of clays overlying sands, gravels and cobbles. Our experience in the area shows the sands, gravels and cobbles are underlain by claystone at varying depths. We expect ground water at about the elevation of Deer Creek will be found under the right abutment and little or no ground water will be found in the clays or claystones under the left abutment. We believe straight-shaft piers penetrating the claystone will be the better foundation for the left bridge abutment due to the expansive clays and claystones. Footings bearing on the sands, gravels and cobbles, straight-shaft piers penetrating the claystone if it is not too deep or friction piling driven into the sands, gravels and cobbles or end-bearing piling driven to “practical refusal” in the claystone are alternatives for the right abutment. However, the larger cobbles and perhaps boulders in the sand, gravel and cobble stratum may interfere with drilling pier holes or driving piling. Pier holes will need to be cased due to the ground water. The existing bridge across the South Platte River appears to have performed satisfactorily, from the foundation point-of-view. We do not know how the existing bridge is founded, but suggest this be learned. Because the existing bridge foundation appears to have performed acceptably, we believe it is reasonable to assume at this stage in the project planning that the abutments of either of the proposed new bridges across the South Platte River can be founded with the same type foundation used to found the existing bridge. The alternatives discussed above for the right abutment of the Deer Creek Bridge are also alternatives for the abutments of the new bridge across the South Platte River. We believe that at a time not too distant in the future, if the Reallocation Study progress to design, borings will need to be drilled along the new roadway alignment and at the selected bridge locations, some laboratory tests will be needed and geotechnical engineering will need to be done to confirm our observations, opinions and conclusions discussed above. We would be pleased to provide these services to the project team at that time. 4 SEAR-BROWN CHATFIELD RESERVOIR REALLOCATION STUDY “ROADWAY ANALYSIS STUDY” CTL I T JOB NO. FC.2998