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E- E] Technical Approarrh ® Page 8 Task 8.2 Perform Laboratory Testing and Analysis of Acquired Cores Following vibracore acquisition, labeling and temporary storage shipboard, the vibracores will be transported from Fort Pierce Harbor to a laboratory facility in Melbourne, Florida. Within seven days of delivery to the laboratory, the vibracores will be split, visually inspected, and logged in detail in accordance with USACE standards. Results of the logging will be reported on USACE Engineering Form 1836 and will additionally be recorded on GTLog' geotechnical logging software. This geotechnical logging software is part of ATM's library of in-house software. Textural classification during core logging will be prepared in accordance with the Unified Soils Classification System, described in ASTM Standard D-2487. Color photographs of the sectioned core will be taken at 1 -foot intervals. Five (5) samples will be extracted at discrete sediment horizons per core, and separate physical composite samples will be extracted from the vibracore down to the limits of visually compatible sediment. All samples (assumes a total of 80 individual samples and 16 composite samples) will be analyzed for grain size and percent mud and gravel. Grain size analysis will adhere to ASTM Standard D-422 for mechanical particle size analysis of the soils. Analyses will be conducted by mechanical sieving utilizing a set of nested screens dividing sediments at %2 phi intervals from —4 to +3.5 phi, inclusive, with the +3.75 phi (#200 mesh screen) added to the nested screen set. Laboratory quality assurance procedures dictate that a replicate of approximately 5% of all samples taken for grain size analyses is undertaken. Grain size distribution of samples processed in accordance with the above procedures will be analyzed using the method of moments and graphic methods as described by Folk (1974). Tabular summaries of each sample will be generated and will report sieve size, phi size, mesh opening size in millimeters, weight of sediment retained in grams, cumulative percent retained, and cumulative percent passing. Sample statistics (e.g., mean, standard deviation, skewness and kurtosis) will also be displayed in the summary tables. A frequency plot of grain size distribution (GSD curve) will be provided for each sample in accordance with USACE Form 2087. Upon completing the above described materials tests and analyses, the cores will be packaged in suitable containers and transferred to the County for permanent storage at a designated location within the County. Task 8.3 Prepare Supplemental Geotechnical Report A Geotechnical and Sand Source Investigation Report will be generated which will detail the field, interpretive and laboratory procedures utilized to acquire and analyze the geophysical riati nPnnhvnic^I „ ri (J� ;i::u, data, vibfacoie fogs and color photographs, sediment analysis data sheets for each sample, percent mud and GSD curves for each test sample analyzed (assuming five samples per core), and the preparation of maps. The above interpretive maps will accompany graphics of the areas investigated from the side scan grid and bathymetric surveys for the north borrow area. One draft and ten (10) final copies of the report will be prepared and submitted to the County.