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Indian River County Sector 3 - Beach Restoration Project Additional Services Scope of Work Part 2 - ENGINEERING & GEOLOGICAL ANALYZES Task 1 — Engineering Analyzes Task la - Bathymetric Survey : COASTAL TECH will perform forty-three (43) profile surveys of the dune and beach to approximately 2000 feet offshore at every FDEP monument from R- 15 to R-57 within the Project Area — in compliance with FDEP permit application and rule requirements. The survey shall include ; ( 1 ) grade elevations at about 20 feet on center - and at breaks in slope, (2) the location of the seaward face of any adjacent existing building, (3 ) the location of the existing vegetation line, and (4) the location of the approximate mean high water line (MHWL) . COASTAL TECH will subcontract this survey work to Morgan & Eklund (M&E) of Wabasso. COASTAL TECH will review the survey for completeness and use the M&E and county surveys as the basis of design and the FDEP permit application. Task lb — Critical Erosion Assessment: Consistent with FDEP rules , COASTAL TECH will perform an assessment of existing data and prepare a Memo summarizing the data and a rational for extension of the of the critically eroded shoreline, as designated by FDEP, from FDEP reference monument R51 .3 to the southern limit of the proposed beach restoration project at monument R55 . The Memo shall "specifically support beach restoration within the segment between R51 .3 and R55 to be in the public interest. " Task lc — Hardbottom Variability Analysis: COASTAL TECH will review the most recent and available LiDAR survey data within the Project Area and compare to published FDEP survey data for the nearest time period . Appropriate criteria will be identified using Foster and Dean statistical analysis "to determine if the recent 2006 bathymetric data is sufficient to map the variability of hardbottom elevations such that an accurate calculation of cross-shore and alongshore spreading of the beach fill can be conducted." COASTAL TECH will revise the existing Design Document to include the analysis results . Task ld —Fill Adjustment & Spreading Analysis: COASTAL TECH previously, under separate authorization, applied the USACE model SBEACH to determine the expected cross-shore adjustment of proposed fill, and the model GENESIS to address the alongshore spreading of proposed fill . To analyze the reliability of SBEACH and GENESIS results , COASTAL TECH will use "profile translation with conservation of volume" and the Dean equilibrium profile to re-assess long-term profile evolution, as well as , Dean 2005 spreading model to cumpare previous predictions of "cross- shore and longshore spreading of beach fill. " COASTAL TECH will revise the existing Design Document to include "the calculations and results of these analyses for the Sector 3 beach fill ." Page 11 of 14 June 13, 2007