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I I I I I I I I I I I I I I I I I I I Review Process: ~ The COE imported each .dxfformatted file into our native working CADD environment, Microstation Ver. SE ~ Accurate translation was verified ~ The COE used InRoads Ver. 7 (Intergraph Civil Engineering software) to import the 3-D graphics from the Microstation files into surface files (dtm's) o Elements were imported either as random points or breaklines ~ The data was triangulated (using InRoads) ~ Contours, spot elevations, profiles, and cross sections were produced (using InRoads - from the created dtm' s) in Microstation files. ~ The digital orthos (SID files) were used as a back drop in the Microstation files ~ These graphic data were visually evaluated. ~ No in-field map accuracy checks were performed Assumptions & Initial Findings: ,( The digital orthos (SID files) tiled correctly and have the resolution and contrast expected from the source photography. ,( The SID files met COE expectations and are serving as the baseline to help judge the dtm data. ,( Digital terrain data for Area I (western most - DTMOl.dxf) provides a reasonable representation of what the ground is expected to look like on a macro scale. However, during detailed review along the river corridor data points that appear inconsistent and possibly in error were discovered. Plates 3,8, 10, 11 show plan view examples of the inconsistent data. These inconsistencies are verified by observation of the corresponding profile plots. ,( Digital terrain data for Area 2 (middle area - DTM02.dxf) showed a series of mounds near the center of the data set. Closer observation of the point data in these areas showed elevation differences of 4 to 6 feet between adjacent data points (in what appeared to be open fields).