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1 <br /> obtained west of the G&O mapping limits at U.S. Highway 36. The low point in U.S. <br /> Highway 36 was found to be west of the limits of the G&O mapping at this location. <br /> ' Additionally, the G&O HEC-2 models assumed that the entire 100-year discharge for <br /> South Boulder Creek crossed U.S. Highway 36 within their mapping limits. Since <br /> ' portions of the Flatiron Property outside of the G&O mapping limits could be inundated <br /> during a 100-year event, it was determined a re-analysis the flood flows that split away <br /> ' from the main channel flows at U.S. Highway 36 should be undertaken. <br /> ' HYDRAULIC METHODS UTILIZED IN LOVE RE-ANALYSIS <br /> Upon completion of the technical review of the G&O model, Love & Associates <br /> determined that the G&O model did not accurately reflect the existing floodplain <br /> conditions of the Flatiron Property. Following a site visit and a complete review of all <br /> ' files pertaining to the G&O analysis, it was apparent that the berm constructed around <br /> the Flatiron Property had not been certified by FEMA as a flood protection levee. It is <br /> FEMA's policy that for the purpose of preparing floodplain maps any levee constructed <br /> for flood protection purposes must meet or exceed all of FEMA's levee criteria as <br /> defined in Sections 60.12, 60.3, 60.4 and 60.5 of the FEMA National Flood Insurance <br /> Program: (Regulations for Floodplain Management and Flood Hazard Identification), <br /> ' revised as of October 1, 1990 a copy of which is attached in the Technical Appendix at <br /> the back of this report. <br /> The Love & Associates' study examined the full extent of the 100-year floodplain in the <br /> ' vicinity of the Flatiron Property utilizing the HEC-2 backwater analysis program <br /> developed by the U.S. Army Corps of Engineers. The Love HEC-2 models were <br /> ' developed using the regulatory (G&O) models supplemented with May, 1993 <br /> topographic mapping in the vicinity of the Property. The U.S. Highway 36 bridge and <br /> ' cross sections downstream of U.S. 36 were modeled using information taken directly <br /> from the regulatory model. <br /> 1 <br /> -12- <br />