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On October 28 , 1994 , John P. Cummings returned to the subject site and measured the depth to groundwater in the wells prior to purging and sampling the Monitoring well MW-1. The groundwater sample was collected via a clean bailer, placed in 40 ml VOAs and 500 ml plastic bottles, labeled, placed in a cooled ice chest and transported to a state certified laboratory (MCCAMPBELL ANALYTICAL INC. ) under COC documentation for analysis. The well data is contained in Appendix B. 1 GRADIENT DETERMINATION ' Prior to purging and sampling, the newly- constructed wells MW-1, MW-2 and MW-3 were surveyed with an arbitrary value of 40. 00 feet ' given to MW-1. Prior to purging and sampling the depth to groundwater was measured by an electronic probe in the three Monitoring Wells on site. The ' water depth was measured from a mark located on the top of the casings. An assumed elevation of 40. 00 feet was assigned to MW-1. The groundwater gradient data are presented in Table 2 . The gradient calculated for the monitoring wells is approximately 2700 at 0. 082 ft/ft. The slope appears to be larger than expected, however this value may reduce as the wells become better developed. The groundwater gradient is depicted in Figure 3 . TABLE 2 Groundwater Elevations (ft) - October 28 , 1994 Well ID Top of Casing Depth to Water Groundwater Elevation ' MW-1 40. 00* 32 . 35 7 . 65 MW-2 40 . 03 33 . 68 6. 35 MW-3 39 . 43 32 .93 6. 50 ' * Assumed elevation ANALYTICAL RESULTS ' The analyses methods are those required in the "Tri-Regional Guidelines" which are directives of the Regional Water Quality Control Board and requested by the SJCEHD. ' The analyses completed were for Total Petroleum Hydrocarbons, as gasoline (TPHG) ; Benzene, Toluene, Ethylbenzene and Xylene (BTEX) ' via EPA Modified Method 8020/8015 and for Lead using the AA methods. r 8