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Beth Mitchel o-Amd-$on Donaldson March 24;"'l995 Page 6 Test Plan Matrix, Expectations and Limits, Vero Beach PEP Reef. Wave Height Reduction - There is no discussion or documentation of what is meant.by "Wave Height Reduction". Is this general wave height reduction? Is this the reduction of the higher one third of the waves measured at the site? Is this for individual waves? The two nearshore gages will have to be located to "track" a wave from the seaward side of the breakwater in a specific depth, to the leeward side of the breakwater in a specific depth., Control gages will also need to be established to determine the effect of shoaling on wave height reduction. The test to be applied to the transmission coefficients will be that the measured average over -a one year period will be less than the expectation: The same criteria shall be applied separately to the higher it of the incident waves occurring over a one year period. Quantification of this parameter will need to be modified as outlined above. Volumetric Changes - This criteria shall be applied immediately landward of the proposed 4,000 feet of breakwater and will not include the gap between the northern and southern components of the entire structure. The lower limit of 5.0 cy/ft/year translates to accumulation on an average annual basis of 20,000 cubic yards landward of the proposed 4,000 feet (not including the gap). The upper limit of -0.5 cy/ft/year translates to erosion on an average annual basis not to exceed 2,000 cubic yards landward of the proposed 4,000 feet (not including the gap). How will the material which is placed as part of the on-going dune maintenance program be included in the volumetric change assessment? Will the quantity placed be deleted on an annual basis? Shoreline Changes - The same comments as stated above for the volumetric changes hold true for the shoreline changes. Shoreline changes shall be analyzed in conjunction with the volumetric data. Limits established for shoreline change, over the monitoring period are: a) if the Mean High Water (MHW) shoreline does not change over the 3 year test period, without adverse effects to the adjacent shordline. b) The lower limit is the Mean High Water (MHW) shoreline achieves an average of 5 feet of beach width increase per year over the 3 year test period for a total of'15 feet. c) The upper limit is that the Hean High Water (MHW) shoreline recedes more than 0.5 feet per year with a total recession of 1.5 feet -for the 3 year period, over any 400 foot segment within the monitored area then the project 28 MARCH 28, 1995