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Exhibit A <br /> Scope of Work <br /> Indian River County Beach Nourishment Project Sectors 1 and 2 <br /> Addendum to Mitigation Plan- July 11 , 2006 <br /> Mitigation Reef Monitoring <br /> The permit for Indian River County Sector 1 and 2 Beach Restoration (Permit No. <br /> 0166929-001 -JC) required construction of five acres of nearshore artificial reef as <br /> mitigation for impacts to the expected burial of 3 . 8 acres of nearshore hardbottom . <br /> Approximately 3 .6 acres of impact was expected to high-relief reef habitat dominated by <br /> sabellariid worm, and 0.2 acres of low-relief, algae-dominated reef were predicted to be <br /> impacted by the beach restoration project. <br /> Two types of mitigation reef were constructed as mitigation for the two habitat types : <br /> high relief, high complexity (HRHC) reef and low relief, low complexity (LRLC) reef. <br /> The high relief, high complexity reef was designed to have a vertical relief of 3 to 6 feet, <br /> and boulders were partially stacked to achieve this vertical relief. The low relief, low <br /> complexity reef was designed to mimic a vertical relief of 1 to 2 feet using a single layer <br /> of boulders. The LRLC mitigation reef was originally sited inshore of the HRHC <br /> mitigation reef. However, the location of the LRLC reef was modified due to sand <br /> movement during Huff icanes Frances and Jeanne in September 2004, which created <br /> shallower water depths and thicker sand layers at the nearshore reef location. The LRLC <br /> reef was moved offshore in alignment with the remainder of the HRHC mitigation reef. <br /> Elimination of the gap between the two reef types did not relieve the County from its <br /> obligation to offset the loss of habitat function provided by both community types, and <br /> the monitoring is designed to evaluate the performance of both reef types as replacement <br /> habitat for the impacted reef type. <br /> Permit No. 0166929-001 -JC required that, if construction of the mitigation reef was <br /> completed after the construction of the beach fill, the mitigation area would be increased <br /> by 0.20 acres per year. Construction of the mitigation was not completed until the <br /> summer of 2005 . Therefore, a total of 4 .96 acres of HRHC reef, consisting of 36, 120 ft. <br /> x 50 ft. units, was constructed; and a total of 0.28 acres of LRLC reef, consisting of two, <br /> 120 ft. x 50 ft. units, was constructed, between approximately R-91 + 600 ft and R-93 + <br /> 700 ft. The LRLC reef is located at the southern end of the reef at R-93 + 700 ft. in <br /> water depths ranging from - 13 to - 16 ft. NGVD, and the HRHC reef is located in water <br /> depth ranging from - 14 ft to - 18 ft. (NGVD). Reef units are separated by 10 foot spacing <br /> to create a 20% sandy bottom within the site for a total of approximately one acre of <br /> sandy bottom. <br /> Modification No. 0129291 -006-EM authorized the placement of an additional 1 .65 acres <br /> of LRLC reef immediately south of the LRLC mitigation reef between R-93 +700 ft. and <br /> approximately 100 ft south of R-94. This additional LRLC reef was constructed in water <br /> depths between - 16 ft. and - 18 ft NGVD. The Department agreed to consider future <br /> 1 <br />