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Mr Harlan Knoll Page 3 of 5 . 1.5 Well Surveying and Groundwater Elevation Determination The newly installed monitoring wells were surveyed by Morrow Surveying a State-licensed land surveyor, on November 14, 2002 using global positioning system (GPS) equipment pursuant to AB2886 Morrow Surveying recorded the latitude and longitude of the site wells relative to the North American Datum (NAD83) and the well casing elevations relative to assumed North American Vertical Datum (NAVD88) A site map showing monitoring well locations, latitude and longitude coordinates and wellhead elevations is included in Attachment C The potentiometric surface was calculated by subtracting wellhead elevations from the respective depth to water measurements Groundwater fell an average of 0 77 feet between September 4, 2002 and November 4, 2002 The potentiometric surface elevation at the site ranged from 1 40 feet (MW7) to 1 94 feet (MW5) above mean sea level Groundwater flowed in a west- northwesterly direction with an average hydraulic gradient of 0 002 ft/ft Groundwater elevations are summarized in Table 1 A potentiometric surface map generated using the November 4, 2002 well monitoring data is depicted on Figure 3 2.0 RESULTS OF INVESTIGATION 2.1 Subsurface Conditions Soil encountered during drilling consisted primarily of fine-grained material from the ground surface to approximately 15 5 to 19 feet bgs, and poorly to well graded sand from 15 5/19 feet bgs to 20 feet bgs, the maximum depth expolored The fine-grained material was generally clay with less than 10% sand from the ground surface to approximately 5-9 feet bgs, and clays and silts with 15%-30% sand from approximately 5/9 feet bgs to the underlying sand unit Groundwater was initially found at depths ranging from approximately 7 5 to 13 feet bgs during drilling Static groundwater was measured at 6 3-7 6 feet bgs Soil boring/well logs are included in Attachment A 2.2 Soil Analytical Results No constituents of concern were detected above laboratory method detection limits (MDLs) in any of the soil samples analyzed from borings MW5, MW6, or MW7 Soil analytical results are summarized in Table 2 Laboratory reports and chain of custody documentation are included in Attachment D 2.3 Groundwater Analytical Results No constituents of concern were detected in groundwater samples collected from wells MW6 or MW7 Methyl tert butyl ether (MTBE) was detected at a concentration of 3 4 parts per billion (ppb) in the groundwater sample collected from well MW5 Groundwater analytical results are summarized in Table 3 The estimated extent of MTBE in groundwater is presented G\Data\GROUNDZE\Barnyard-Manser\ReportslWELLS RPT MW 5 G 7 doc