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I 1 Mr Nuel Henderson Page 5 of 9 Groundwater Sampling ' Water Ievels in new wells MW1313, MW15A through MW15C, MW16A and MW16B were monitored on January 30, 2003 Water level data are summarized in Table 2 1 The new wells were purged and sampled on January 30 and 31, 2003 Prior to sampling, at least three well casing volumes of groundwater were purged from each new well During the purging ' process temperature, pH, and electrical conductivity parameters were measured Purging continued until these parameters had stabilized Groundwater samples were collected from each well subsequent to parameter stabilization and a minimum of 80% recovery to pre-purge levels ' using a disposable bailer The samples were transferred to the appropriate containers, sealed, labeled, and immediately placed in an ice chest cooled to a temperature of approximately 40C The samples were transported to Argon under chain of custody protocol for the analysis of TPHg, ' BTEX, gasoline oxygenates, EDB and 1,2 DCA using the appropriate EPA methods ' RESULTS Soil Lithology '• Well MW13 was deepened and renamed MW13B Soil logging was initiated at a depth of 75 feet bgs At intervals of 75-76 5180 feet bgs and 76 5/80-815 feet bgs, soil in well MW13B was ' identified as silty clay and well-graded sand with clay,respectively Except for two sand beds identified at 415/45 feet bgs to 46 5150 feet bgs ("A Sand"), and 60 ' feet bgs to 75 feet bgs ("B Sand"), silts and clays were the predominant soil types classified in wells MW16A and MW16B ' In well MW15A, a poorly-graded sand with clay was identified from 36 5140 — 46 5150 feet bgs This is believed to correlate to the A Sand in the wells further west The B Sand was logged in well MW 1513 between the depths of 60 feet and total depth of 81 5 feet The mud-rotary drill ' cuttings returned in well MW15C indicated the B Sand to be present between approximately 60 and 78 feet The A Sand was not noted to be present in this well Beneath the B Sand in well MW15, fine-grained materials were present to total depth of 121 feet except for two very thin ' sand beds a four-inch thick sand stringer at a depth of 106 feet and a one-foot thick clayey sand at 118-119 feet ' Boring logs for the new wells are included in Attachment A ' 11GZA_FSIVOL_MATA1GROUNDZE1ROEKICLOSURE"Repwfts\Add_HSA Mud wells doc I