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7. The unit costs for the opinion of probable construction cost were obtained by comparing recent bids of current roadway construction projects located in the Front Range. The costs were from publicly bid projects and are adjusted based on engineer's judgment where appropriate to be consistent with the level of work expected for this project. Investigations On December 19, 2003, a site visit was held with EDA W, CWCB, Sear-Brown, and CTL Thompson to make a visual observation of the existing soil conditions along the proposed alignment. Mr. Frank Holliday, CTL Thompson, was selected to perform this review and provide his conceptual level recommendations based on his knowledge of and experience with the soils in this part of the Denver area. Mr. Holliday made a visual reconnaissance of the types of soils present along the proposed roadway alignment to attempt to identify areas of potential concern that may impact the feasibility or cost of constructing a roadway along the alignment. Mr. Holliday's observations generally indicate that the soils northerly of the Deer Creek crossing appear to be clay over claystone bedrock which are expansive type soils. For the roadway southerly of Deer Creek appear to be a variable thickness of clays overlying alluvial sands and gravels mixed with some cobbles and probably boulders. Mr. Holliday provided some possible methods to deal with potential construction issues but did not observe any geologic or geotechnical conditions that would preclude building the roadway in the proposed alignment on the conceptual plan. For the complete text of CTL Thompson's observations, refer to the letter dated January 6, 2004 from CTL Thompson to Sear-Brown. Route Selection . In the original concept plan there were two possible roadway alignments that were reviewed by the design team. Both alignments were identical along the west side of the existing reservoir to the point where the current roadway turns easterly around the southern side of the reservoir towards the Platte River crossing. At this point one option was to use this existing alignment and significantly raise the roadway above the new water elevation and effectively creating a causeway across the south end of the reservoir including a new bridge crossing of the Platte River. The second option was to construct a new roadway around the south end of the what would be the new reservoir water levels and make a new crossing of the Platte River. Both of these alignments were reviewed with State Parks and the design team and it was decided by State parks that for operational concerns it would be preferable to construct a new roadway around the south end of the expanded reservoir rather than to build a causeway across it. To that end, a conceptual level design and cost estimate was completed for only the option of extending a new roadway around the south end of the expanded lake. The selected route would be a new roadway approximately 4.1 miles in length including two new bridges.