ARCHIVED REPORTS 2nd QUARTER 2011 QUARTERLY REPORT

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01 August 2011 AGE-NC Project No. 07-1536 Page 2 of 4 2.55 feet (MW-5) to 7.75 feet (MW-3) below the top of the casing (btoc) in the shallow zone and 3.71 feet (MW-7) to 26.00 feet (MW-11) btoc in the deep zone. Ground water elevations at the site ranged from 12.31 feet below mean sea level (MSL) in well MW-4 to 3.75 feet above MSL in well MWA 2 in the shallow zone and from 16.96 feet below MSL (MW-11) to 17.62 feet below MSL (MW-8) in the deep zone. Ground water elevation from well MW-9 was not utilized in contouring the ground water elevation, as the current casing elevation is not documeted . Previous and current depth to water and ground water elevation data is summarized in Table 2. • On 30 June 2011, the depth to ground water in well MW-14 was approximately 2.40 feet btoc; the ground water elevation in well MW-14 was determined to be 14.38 feet below MSL (Table 2). • First encountered ground waterflowwas inferred to be toward the east to southeast down the slope of the levee at well MW-11 and MWA 3, at a calculated hydraulic gradient of 0.22 foot/foot (ft/ft) in the area of the levee and toward east at a range of calculated gradients between 0.36 ft/ft and 0.14 ft/ft (Figure 3). • The ground water flow inferred from deep-screened (50 feet to 60 feet bsg) wells MW-6, MW-7, MW-8 and MWA 1 (70 feet to 80 feet bsg) was southeast at a calculated gradient of approximately 0.004 (Figure 4). • During a previous free product removal conducted at the site on 12 November 2010, approximately 0.01 feet (minimal) of free product was measured in well MW-2 (Table 4). Free product, was removed from well MW-2 using a disposable bailer. No free product was noted in well MW-2 during the first and second quarter monitoring events (Table 4). • During the 29 June 2011 monitoring event,total petroleum hydrocarbons quantified as gasoline(TPH-g)were reported in the ground water samples collected from wells MW-2, MW-4 and EW-1 at concentrations of 11,000 micrograms per liter (Ng/1), 2,300 pg/l and 300 pg/l, respectively. Total petroleum hydrocarbons quantified as diesel (TPH-d)were reported in the ground water sample collected from well MW-2 at a concentration of 19,000 pg/1. • Ethylbenzene and total xylene compounds were reported in the ground water samples collected from wells MW-2 and MW-4 at maximum concentrations of 6.3 pg/I and 49 pg/I, respectively in well MW-2. • The fuel additive methyl tertiary butyl ether (MTBE) was reported in the ground water samples collected from wells MW-2, MW-4, MW-5 and EW-1 at concentrations of 15 pg/1, 33 pg/I, 5.3 pg/I and 10 pg/1, respectively. Advanced CeoEnvironmental,Inc.