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Mr Martin Harris Page 5 of 7 • An experienced field technician measured the depth to groundwater in monitoring wells MW I through MW11D on March 28, 2005 Groundwater elevations were calculated by subtracting the measured depth to groundwater in each well from the respective wellhead elevation The depth to groundwater in the wells ranged from 4 13 to 5 85 feet below the tops of the well casings (btoc) The potentiometric surface in site wells rose an average of 1 04 feet between December 10, 2004 and March 28, 2005 As measured on March 28, 2005, shallow groundwater beneath the site generally flowed northwest at a gradient of 0 0009 feet per foot A potentiometric surface map generated from the March 28, 2005 monitoring data is shown on Figure 3 Groundwater monitoring data are summarized in Table 2 Monitoring data sheets are included in Attachment E Monitoring wells MW1 through MW11D were purged and sampled on March 28 and 29, 2005 The wells were purged of at least three well casing volumes pnor to sampling The physical parameters of temperature, pH and electrical conductivity were measured during the purging process Groundwater samples were collected after the physical parameters stabilized and groundwater in the wells recovered to pre-purged levels The samples were placed into an ice chest refrigerated to approximately 4°C and transported to Argon Laboratories under chain of custody protocol Well purge logs are included in Attachment E RESULTS OF INVESTIGATION Subsurface Conditions In each boring, silty sand was present from the ground surface to a depth of ten feet bgs Beneath this surficial unit, an interval of poorly graded sand is present to depths between approximately 15-20 feet A fine-grained (silt and clay) unit underlies the sand to the bottom of each hole in borings MW8, MW9 and MW10 These findings were confirmed by the CPT investigation performed during the drilling of MW11D Soil was generally sand and gravelly sand from approximately 20 feet bgs to at least 38 feet bgs near wells MW 10 and MW 11 D No hydrocarbon odors or elevated PID readings were observed in any of the soil borings Saturated soil was encountered at 5 feet bgs in each boring Boring logs describing the lithology are included in Attachment C A copy of the CPT log is included in Attachment B Soil Analytical Results Soil samples selected for analysis from wells MW8 through MW11D were analyzed by Argon for TPHg, BTEX, and oxygenated gasoline additives including EDB and 1,2-DCA No constituents of concern were detected in any of the soil samples collected Soil analytical results are summarized in Table 1 A copy of the laboratory report including chain of custody • documentation is included in Attachment F G 1GROUNDZLITuffBo,lRepartslQMR1200513 QM2005 doc