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GEOIVIATFtIX During well development, the electrical conductivity, pH, temperature, and clarity of the development water were monitored A 2-foot thick bentonite seal was placed above the filter pack and hydrated The remainder of the annulus, from the top of the bentorute seal to the ' ground surface, was filled with a cement-bentonite grout The top of the well casing is fitted with a locking cap A 12-inch or 8-inch diameter steel well monument, with a traffic-rated ' steel cover, was set in cement The well completion is flush with existing site grade The locations and elevations of the new monitoring wells were surveyed by Dillon & Murphy Engineering of Lodi, California, on February 20, 2003 Well construction data are ' summarized in Table 1, and well completion diagrams are included in Appendix A ' 3.3 SAMPLING OF MONITORING WELLS FOR REMEDIATION EVALUATION Groundwater samples were collected from the three existing and three new monitoring wells ' to evaluate intrinsic bioremediation of petroleum hydrocarbons in groundwater at the site Groundwater sampling was conducted by Geomatnx personnel on February 20, 2003 Prior to ' sampling each well, the presence of separate-phase petroleum hydrocarbons was assessed using an interface probe, and the water levels on the wells were measured using an electric sounder No floating product was detected in the wells Subsequently, a minimum of three casing volumes of water were purged from each well using a submersible pump The purge pump was decontaminated between each well Purging and sampling were conducted in the ' fallowing order MW3-4, MW3-5, MW3-6, MW3-1, MW3-3, and MW3-2 (from the well with the anticipated lowest concentrations to that of the highest concentrations of petroleum ' hydrocarbons) to prevent cross contamination Field parameters (i e , electric conductivity, pH, oxidation-reduction potential [ORP], dissolved oxygen [DO], and temperature) were ' measured during well purging, and groundwater samples were collected after field parameters had stabilized Disposable bailers were used to collect the groundwater samples for laboratory analysis of VOCs, and a low-flow submersible pump was used to collect the groundwater ' samples for inorganic compounds ' Groundwater samples were preserved and transported under chain-of-custody procedures to APPL for analyses Groundwater samples from the three existing monitoring wells were analyzed for TPHg using U S EPA Method 8015 and BTEX using U S EPA Method 8260B Groundwater samples from the three new monitoring wells were analyzed for TPHg using U S EPA Method 8015, 12DCA, BTEX, and oxygenates (including MtBE) using U S EPA Method 8260B, and dissolved lead using U S EPA Method 6010B, as requested by the I 1PRQIECTVOWA6437 00016437-08 doc 8