ARCHIVED REPORTS 2nd QUARTER 2011 QUARTERLY REPORT

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Site Background Information: Herman and Helens Marina Page 10 of 13 • HU7: Grab ground water samples CPT2-85 and CPT4-86 were collected from HU7. TPH-g was detected in both samples at concentrations of 170 pg/I and 140 pg/I, respectively. BTEX compounds were detected in both samples at maximum concentrations of 10 pg/I toluene, 3.5 pg/I ethylbenzene and 23 pg/I xylenes, in sample CPT2-85. MTBE was detected in both samples at 74 pg/I and 120 pg/I, respectively. • HUB: Grab groundwater samples CPT1-96,CPT2-98 and CPT3-105 were collected from HU8. TPH-g was detected in samples CPT2-98 and CPT3-105 at concentrations of 140 pg/I and 1,500 pg/I, respectively. BTEX compounds were detected in samples CPT2-98 and CPT3-105 at maximum concentrations of 320 pg/I benzene, 700 pg/I toluene, 140 pg/I ethylbenzene and 560 pg/I xylenes, in sample CPT3-105. MTBE was detected only in sample CPT2-98 at a concentration of 43 pg/l. • No additional analytes were detected at or above laboratory detection limits in the ground water samples analyzed. None of the analyzed compounds were detected at or above laboratory detection limits in the ground water samples collected from borings B14 and CPT-1. Additional information can be found in the AGE-prepared Additional Site Assessment Report-April 2004, dated 19 April 2004. SITE CONCEPTUAL MODEL Based on the site assessment activities to date, AGE has developed a site conceptual model for the release, migration and distribution of the contaminants in the subsurface as described below: The site is essentially flat land, with a 20-foot high levee on the western edge. The levee is composed essentially of anthropomorphic, built-up levee material ranging from clay and silt adjacent to the slough to coarser-grained sands and road-base material. A peat layer underlies the levee deposit and forms the surface layer of the flat land towards the east (HU 1); the peat layer ranges in thickness from approximately 6-foot thick east of the ASTs to 20-foot thick beneath the levee material. From the base of the peat layer to the total depth of soil borings,the soil stratigraphy consists of interbedded sand and silty clay/clayey silt layers; sand layers were identified at approximately 30 feet, 70 feet, 93 feet and 102 feet below the maximum surface grade (bmsg), as measured from the top of the levee, and fine-grained soil at approximately 40 feet, 83 feet and 95 feet bmsg. Since initiation of ground water monitoring in September 1997, ground water elevations in the flat land have ranged from approximately 18.5 feet to 12.5 feet below mean sea level (MSL). The ground water elevation on the levee ranged from 3 to 5 feet above MSL Advanced GeoEnvironmental,Inc.