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more complete details As a result of that work, quarterly groundwater monitoring was initiated - there have been four (4 ) measurements taken since the placement of those wells. The latest quarterly report, prepared by WJH & dated March 11 , 1994, includes a summary of all of the laboratory analyzes, groundwater levels & hydraulic gradient data obtained to date. The data collected suggested the possibility of an offsite source of contamination located to the west or north of the property. A thorough title search of selected properties was conducted to determine if there might be other, previously unidentified sources of contamination The results of that survey were incon- clusive - no record of any UST placement or removal were found There is a currently active gasoline station & convenience store immediately adjacent to the property on the southeast corner Although the County EHD does not have any records of environ- mental problems associated with the site, its ' proximity to the Sanchez property warranted further investigation. Because of the shallow water table, (22 ' bgl, ) it was felt that a soil gas vapor survey might reveal whether that site was a possible source, or indicate the direction of other possible sources . On January 31 , 1994, WJH prepared a workplan to conduct an investigation within the limits of the Sanchez property in an attempt to evaluate such other possible sources The results of that work is discussed below DISCUSaION OF RESULTS QE ,HE SOIL GAS VApOR INVESTIGATION- Under the direction of WJH, Don Light of Del-Tech Geotechnical services performed the work on March 12 & 13 , 1994 as detailed in the workplan Due to surface conditions & test results, some of the proposed locations were not utilized Operations were witnessed by Michael Collins of the EHD The field procedures used by Dei-Tech are detailed in EXHIBIT A_ The final locations of the soil probes are shown on PLATE I . (prepared by Del-Tech, ) and reveal that only locations #1 , 2, 4 , 5 10, & 13 produced readings on the PID meter The highest readings were recorded from locations 01, 4, & 5, all in the immediate vicinity of the site of the removed UST' s Based on the results of this work, the nearby gasoline station does not appear to be a possible source of contamination The four hydraulic gradient measurements taken since the place- ment of the wells, (refer to PLS II for details, ) are all in 2