ARCHIVED REPORTS 2nd QUARTER 2011 QUARTERLY REPORT

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Site Background Information: Herman and Helens Marina Page 4 of 13 to lean clay near the top of HU3 is classified as HU313. The overall unit is characterized by fluctuating pore pressures ranging from low in silty clays and clayey silts to high in the silts. A pore-pressure dissipation test in clayey silt/silt at 43 feet bsg in CPT-4 showed a steep decrease in pore pressure within 400 seconds (t50 = 1.7 min), corresponding to low hydraulic conductivities ranging between 5x10"5 to 10-7 cm/sec, which are values that are typical of silt mixtures and very stiff, fine-grained soil (Robertson and others, 1986). Hydrostratigraphic Units 4 (HU4), 6 (HU6) and 8 (HU8) extend from approximately 70 to 83 feet, 93 to 95 feet and below 102 feet bmsg, respectively, and consist mainly of fine-to medium-grained, poorly-graded sand. Pore pressureswithin these intervals are consistently low. Hydrostratigraphic Units 5 (HU5) and 7 (HU7) extend from 80 to 90 feet and 96 to 102 feet bmsg, are composed mainly of silts. These intervals are characterized by uniformly high pore pressures; a pore-pressure dissipation test in the silt at 70 feet bsg in CPT-4 showed a slow decrease in pore pressure over approximately 3,000 seconds (t50 = 8.3 min), corresponding to very low hydraulic conductivities ranging between 5x10 to 2x10.8 cm/sec, which are values that are typical of silty clay and clay, and very stiff, fine-grained soil (Robertson and others, 1986). SITE ASSESSMENT ACTIVITIES On 22 August 1995, three hydropunch soil borings (HP-1, HP-2 and HP-3)were advanced at the site. TPH-g and BTEX were detected in soil and ground water samples collected from each boring, at maximum concentrations of 300 mg/kg TPH-g, 190 mg/kg TPH-d, 1.2 kg/mg benzene, 3.1 mg/kg toluene, 5.5 mg/kg ethylbenzene and 22 mg/kg in soil sample HP-1-11', and 1.0 micrograms/liter (Ng/1) TPH-g, 0.24 pg/I TPH-d, 260 pg/I benzene, 8.4 pg/I ethylbenzene and 36 pg/I xylenes in water sample HP-1). On 29 August 1996, five probe borings were advanced at the site. TPH-g, BTEX and methyl-tertiary butyl ether (MTBE) were detected in the soil and ground water samples collected from the borings advanced in the northern portion of the site. On 10 September 1997,fourground water monitoring wells(MW-1, MW-2, MW-3 and MW- 4)were installed at the site to investigate and monitor the lateral extent of impacted ground water. TPH-g, BTEX, and MTBE were detected in the soil samples from borings MW-2 and MW-4. TPH-g, BTEX, MTBE, tertiary amyl methyl ether(TAME) and tertiary butanol (TBA) were detected in the ground water samples collected from the wells on 18 September 1997. Ground water elevation data at the site indicated that the ground water was being controlled by the active island drainage pumping system adjacent to the site. Advanced GeoEnvironmentnl,Inc.