ARCHIVED REPORTS 2nd QUARTER 2011 QUARTERLY REPORT

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Site Background Information: Herman and Helens Marina Page 11 of 13 through March 2001 (MW-1), and was 3 feet above MSL during December 2003 in MW-12. Ground waterflow has consistently been east-southeast, at relatively steep gradients in the immediate area of the levee and low to very low gradients east of the existing ASTs. Site assessment activities to date defined an area extending from the former UST location on the levee eastward to the southern half of the AST enclosure where soil is impacted by high concentrations of petroleum hydrocarbons. The highest petroleum-hydrocarbon concentrations, up to 4,800 mg/kg TPH-g, were detected beneath the former USTs, at the time of their removal; high concentrations of petroleum hydrocarbons, up to 4,000 mg/kg, also were detected in the area of soil borings B11, B16 and MW-6. MTBE is the only fuel component detected at higher concentrations at a location (MW-6 and 136) other than at the former USTs. Based on AGE interpretation of the available data, the initial release(s) of petroleum hydrocarbons occurred from the former USTs priorto their removal in 1991. Once released to the subsurface, the contaminants migrated through the apparently sandy levee material to a vertical depth of approximately 20 feet bsg, at which point the contaminants encountered the less permeable peat (HU1) and began to migrate laterally as well as vertically; lateral migration was eastwards, in the direction of ground water flow, towards the southern portion of the AST enclosure. At the former USTs location, vertical contaminant migration continued to depths in excess of 120 feet bmsg; AGE attributes this deep vertical migration as a consequence of a strong vertical component of recharge from the immediately adjacent Little Connection Slough. The low to nondetectable MTBE concentrations in the former UST area may be an effect of the elevated location of the former USTs. Meteoric waters and seepage from the Little Connection Slough, along with a tidal influence, may have flushed MTBE from the shallow vadose zone. The steep gradient caused by the slough and levee (0.25 ft/ft) transported the dissolved MTBE eastward to the area east of the ASTs, where AGE's ground water maps illustrate gradients ranging from 0.027 ft/ft to 0.085 ft/ft between the wells east of the levee. This interpretation is consistent with the following site history: • The USTs were utilized from around1960 up to circa 1991, well into the age of MTBE usage in gasoline; • The highest petroleum-hydrocarbon impacts (including both TPH-g and TPH-d) to soil are at the former UST location; • Prior to the third quarter 2007 (see below), there have been no documented releases of fuels from the current AST system - based on the TPH-g and TPH-d distribution patterns in soil, the releases from the ASTs would have to include both TPH-g and TPH-d; • There have been no repairs of the AST system since inception of use; and Advanced GeoEnvironmen[aI,Inc.