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Indian River County Page 4 Project No . 00- 11493 ' Detailed graphical profiles of the SPT boring results are presented on attached Sheet 2A, Auger Borings A total of 6 auger borings, all drilled at Pelican Island, were . completed for this study. Four were made to a depth of . 12 feet using truck-mounted equipment, . and 2 . to a depth of 6 feet using hand-turned augering equipment. The hand-auger borings were performed at locations that the . truck could not access . Grab samples of recovered soils were collected from the auger j equipment at intermittent depths, sealed in . moisture-proof . containers , . and taken to our laboratory where they were assigned a USCS group. symbol. Generally,Ahe auger boring .-found soils that are consistent with those reported by the SCS. . An approximately 1 /2' to 24 /2 foot thick surficial layer of dark-colored soil sli htl 'or anic to g Y g (topsoil) ) sand was found to mantle the areas . Below this, brown and gray fine sand containing trace' to slight amounts of silt-size fines and varying amounts of shell fragments was encountered to ' the limits of the borings : Detailed graphical profiles of the auger , boring results are presented on attached Sheet 2B : Permeability Testing One field boreholepermeability test was performed at the location of Auger Boring No. AB-3 using the methodology advocated by the South Florida Water Management District ' (SFWMD) . The borehole permeability, test set-up involved hand-angering an approximately 44 /2 inch diameter borehole to a depth of about 7- 1 /2 feet, inserting a 546ot length of 24nch diameter well screen into the borehole, and then constructing a filter pack in, the annular ' space of the borehole with uniformly graded sand . An approximately 3 -foot length of solid (riser), 2-inch diameter PVC pipe extended from the top of the well screen to a point about 1 /2-foot above the ground surface: The test was conducted by charging the hole with water and then * maintaining the water at a constant level while recording the volume- of water required to maintain , that level at . fixed time intervals . Upon completion of the constant-head test, a falling-head test was . conducted by re-filling the pipe and then recording the water , level drop over a measured time period: Complete test data, including subsurface and" 'hydraulic conditions, are given on the Field -PermeabilityTest sheet provided in Appendix. A. Reference . to the results shows that a . coefficient of permeability of 34 feet per day. (fpd) was determined based on an, average of the constant. and falling-head test results . . Review of the subsoil stratigraphy at 'the test location suggests that the measured permeability is indicative of the horizontal movement of the water through the sand layer.