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Mr Michael Infurna Page 4 of 5 RESULTS Subsurface Conditions Borings MW4 and MW5 were drilled to depths of approximately 31 5 feet below ground surface (bgs) The borings were subsequently constructed into groundwater monitoring wells In borings MW4 and MW5, silts and clays extend from the surface to 21 feet bgs, and from the surface to 26 5/30 feet bgs , respectively Poorly graded sand with clay overlies silty clay to a depth of 21 5/25 feet bgs in boring MW4, and from 26 5/30 feet bgs poorly graded sand extends to unknown depths in both borings MW4 and MW5 Stratigraphy of borings MW4 and MW5 generally correlates to borings drilled during previous subsurface investigations at the site Groundwater was first found at depths of approximately 19 and 20 5 feet bgs in borings MW4 and MW5, respectively Static water levels were measured at approximately 17 feet bgs in both borings No petroleum odors were noted, and no abnormal soil discolorations were apparent in the samples collected from either boring MW4 or MW5 PID readings from soil samples collected ranged from 0 2 parts per million (ppm) to I 1 ppm (PID background = 0 3 ppm to 0 8 ppm) Soil boring/well logs are included in Attachment A On August 20, the potentiometric surface ranged from 10 59 to 10 71 feet below mean sea level Groundwater flowed in a northeasterly direction with a hydraulic gradient of approximately 0 001 - 0 002 ft/ft Groundwater elevations are summarized in Table 3 A potentiometric surface map generated using the August 20, 2002 well monitoring data is depicted on Figure 2 Soil and Groundwater Analytical Results All soil samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) and total petroleum hydrocarbons as diesel by EPA Method 8015, benzene, toluene, ethylbenzene (BTEX) by EPA Method 8020, and for oxygenate additives by EPA Method 8260 In addition, the samples collected from the capillary fringe were analyzed for 1,2-dichloroethane (1,2-DCA) and ethylenedibromide (EDB) by EPA Method 8260 and for total lead by EPA Method 6010 None of the soil samples contained any detectable concentrations of any analyte except for lead The lead concentrations appear to be at naturally occurring background levels Soil analytical results are summarized in Table 1 Laboratory reports and chain of custody documentation are included in Attachment C Each groundwater sample was analyzed for TPHg, TPHd, BTEX, oxygenates, 1,2-DCA, EDB and dissolved lead by appropriate EPA Methodologies No detectable concentrations of any analytes were found Groundwater analytical results are summarized in Table 2 Laboratory reports and chain of custody documentation are included in Attachment D i G\Data\GROUNDZEIWOOLSEY CHnRepotlsMELLRP'r_MW4_MW5 doe