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Mr. Michael Fuchs, P.E. <br /> February 9, 2012 <br /> Page 2 <br /> PROPOSED METHODOLOGY <br /> D&A will perform a clear day dam failure analysis for the dam at Fuchs Reservoir and route the <br /> resulting outflow hydrographs downstream using HEC-HMS. Breach parameters shall be estimated in <br /> accordance with methodologies recommended by the Office of the State Engineer,Dam Safety <br /> Branch. Hydraulic parameters including width of flow, depth of flow, and velocity of flow at critical <br /> locations shall be estimated using the Corps of Engineers' HEC-RAS computer model. A steady-state <br /> water surface profile resulting from the peak flow rates at various locations shall be generated. <br /> Topographic information for the floodplains shall be based on USGS 10-meter DEMs from the <br /> National Elevation Dataset(NED) elevation data. NED data was initially derived from the USGS 7.5- <br /> minute quadrangle elevation data and was then processed to filter out production artifacts from the <br /> existing data. The NED is updated every two months to include new and improved elevation source <br /> data and is considered the best available raster elevation dataset. D&A has the ability to contour the <br /> DEM at any desired interval using 3D Analyst in ArcGIS. The quality of the output elevation contours <br /> shall be controlled by comparing the index contours to the USGS 7.5-minute topographic images. <br /> It is anticipated that field surveys of critical bridges in the study reach will not be necessary. A <br /> meeting shall be held with Matt Gavin of the Colorado Division of Water Resources to present <br /> preliminary dam breach parameters, water surface profile modeling, and inundation mapping and to <br /> discuss if field measurements are necessary for critical bridges. <br /> Inundation maps of the clear day failures of the dam shall be overlaid on 1-meter resolution aerial <br /> photography. <br /> DELIVERABLES <br /> The deliverables for this project shall include a letter report for the inundation mapping analysis <br /> (stamped by a Colorado P.E.), 10 hard copies of the inundation maps, and 2 CDs containing: digital <br /> files of the inundation limits that are compatible with ESRI ARCView software,PDF file of the <br /> inundation maps, and supporting spreadsheets and hydraulic/hydrologic models. <br /> SCHEDULE <br /> Work on this project will begin in March 2012 with delivery of the final product no later than June 15, <br /> 2012. <br /> COST <br /> Assuming that the inundation mapping does not extend downstream of the limit discussed,the <br /> estimated cost for completing these task items is $12,000. This estimate is summarized in the attached <br /> Table 1. The work shall be performed on an hourly basis for services rendered with a not-to-exceed <br /> fee of$12,000. In the event that additional services are requested,the Company shall be advised of the <br />