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Work Plan of 3/17/2000. Monitoring wells were installed in both of these soil bores.The Work Plan of 3/17/2000 also included a soil bore and monitoring well (MW#4) to be installed in the sidewalk 4• on the north side of Lafayette Street. This soil bore was not completed as planned. An unknown 1 underground storage tank was encountered in the direct path of the soil bore. As a result of this encounter, the soil bore was abandoned and the local agencies were notified. A recap of the results of sample analysis for MW#5 and MW#6 are attached. CPT43 was installed on June 13,2000 in the Caltrans right of way. This CPT is northeast of the site, and the data gathered is attached. All monitoring wells have been sampled quarterly, and a recap of the findings is attached. A Work Plan to expand the horizontal definition of the contamination plume was approved in December of 2000 and has been submitted for preapproval to the state fund. PROCEDURE On December 22, 2000, Del Tech Geotechnical Support Services secured water samples from the monitoring wells on the above stated property. The work was supervised by Foothill Engineering. All monitoring wells were in good condition and samples were taken using the standard recommended procedures.All samples were extracted using the tube with check valve pump system. Purge volumes and the physical properties of the ground water are attached in the Del-Tech field log. The replacement and original monitoring wells were sampled for analysis and the original monitoring wells were used to establish groundwater elevation and gradient. (•` All samples were transported under chain of custody to Sherwood Labs of Hilmar, California for analysis by EPA methods 602 and 5030/8015. All water sample analysis and groundwater elevations are summarized in the attached tabular recap sheet. Original data sheets from the laboratories are attached. FINDINGS The groundwater elevation in all of the wells has lowered +/- 0.6 feet from the Iast sampling date (8130/00). MW-I was analyzed to have the highest concentration of gasoline contamination(TPHg) at 127,000 ppb which is an increase from 109,000 ppb on 8/30100. MW-1R produced groundwater samples with higher levels of TPHg than the sample taken 8/30/2000. The groundwater hydraulic gradient was calculated at S=0.003 with the down slope in the Northeast direction (see a site map attached). CONCLUSIONS The groundwater elevation in all of the wells is approximately 0.8 feet lower than the last sampling event. It is typical for Fall groundwater elevations to be lower than Spring and Summer elevations in the City of Stockton. With the exception of MW-1 and MW-1R, most of the monitoring wells were lower in concentrations of TPHg compared to the last sampling event. 2