Attachment B - Report of Geotechnical Exploration Samson Oceanfront Park Revised

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FIELD PROCEDURES Standard Penetration Test (SPT) Borings The SPT borings are performed in general accordance with ASTM D-1586, "Penetration Test and Split-Barrel Sampling of Soils." A rotary drilling process is used and bentonite drilling fluid is circulated in the boreholes to stabilize the sides and flush the cuttings. At regular intervals, the drilling tools are removed and soil samples are obtained with a standard 2-feet long, 2-inch diameter split-tube sampler. The sampler is first seated 6 inches and then driven an additional foot with blows of a 140-pound hammer falling under its own weight a distance of 30 inches. The number of hammer blows required to drive the sampler the final foot is designated the "Penetration Resistance." The penetration resistance, when properly interpreted, is an index to the soil strength and density. SFWMD Percolation/Infiltration Test At the selected test location a borehole was advanced by drilling with clean water to the desired test depth. A slotted casing was set in the borehole to maintain its diameter. Clean water was again introduced inside the casing and the level was allowed to rise to the ground surface. The amount of water added each minute for the duration of the test was then recorded. When the inflow rate stabilized, typically after a period of at least 15 minutes, the test was terminated. The data (borehole diameter, test depth, approximate ground water level, inflow rate) was then used to calculate the hydraulic conductivity in accordance with the South Florida Water Management District Permit Information Manual (Volume IV). LABORATORY PROCEDURES Water Content The water content is the ratio, expressed as a percentage, of the weight of water in a given mass of soil to the weight of the solid particles. This test is conducted in general accordance with FM 1-T265. Percent Organics (Organic Loss on Ignition) The amount of organic material in a sample is determined in this test. The sample is first dried and weighed, then ignited and reweighed. The amount of organic material is expressed as a percentage of the total dry weight of the sample prior to ignition. This test is conducted in general accordance with FM 1-T267. Fines Content In this test, the sample is dried and then washed over a No. 200 mesh sieve. The percentage of soil by weight passing the sieve is the percentage of fines or portion of the sample in the silt and clay size range. This test is conducted in general accordance with ASTM D-1140.