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07 May 2014 • AGE Project No. 09-1692 Page 2 of 3 Total petroleum hydrocarbons quantified as diesel (TPH-d) were only detected in groundwater samples collected from well MW-4 at a concentration of 140 micrograms per liter (pg/1). No additional analytes were reported above laboratory detection limits in the groundwater samples analyzed. Analytical results of water samples collected in April 2014 are summarized in Table 3. The laboratory reports (CTEL Lab Project No. CT214- 1404070), quality assurance/quality control report, and chain-of-custody form are included in Appendix D. The laboratory reports electronic data file (EDF) and depth to water data will be uploaded to the State Water Board's Geotracker database. 4.0. SUMMARY AND CONCLUSIONS Based on the results of this investigation, AGE presents the following conclusions: • In April 2014, the average groundwater elevation was 5.23 feet below NAVD; the average groundwater elevation at the site increased approximately 0.21 feet since the previous sampling event in December 2013. • Consistent with past monitoring events, groundwater was inferred to be flowing radially towards a groundwater depression centered at well MW-4, at nearly flat hydraulic gradient during the April 2014 event (Figure 3). • During the April 2014 groundwater monitoring event, TPH-d were detected in groundwater samples collected from well MW-4 at a concentration of 140 Ng/1. The lateral extent of dissolved TPH-d is defined (Figure 4). • TPH-d concentrations in wells MW-2 and MW-4, the historically impacted wells, have decreased over the past five sampling events dating back to December 2011. During April 2014, TPH-d concentrations remained non-detect in well MW-2 for the second consecutive sampling event and decreased to 140 pg/I in well MW-4. TPH-d concentrations exhibit a decreasing trend in well MW-4. Graphs illustrating TPH-d concentration trends in wells MW-2 and MW-4 are included in Appendix E. 5.0. RECOMMENDATIONS Based on the findings of the environmental activities recounted in this report, AGE recommends the site be considered for closure as a low-threat groundwater case. Advanced GcoEnvironmental Inc.