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7.0 Conclusions and Recommendations Wright has completed the Groundwater Monitoring Well Installation and Initial Groundwater Sampling and Chemical Analysis, 3`a Quarter 2009 was prepared for submittal to the City and PHS/EHD and RWQCB Region 5. One monitoring well was installed on the WWTP property at the location discussed with SJCEHD. The new well, MWWES-1 was sampled for analysis, and four existing monitoring wells (MWHP-5, MWHP-6, MWHP-7 and MWHP-8) were used for groundwater measurements only in order to plot groundwater flow direction. The initial groundwater elevation contour plot flow showed a northwest flow direction at a calculated gradient of 0.0007. The groundwater sample analysis showed that TPHD was detected 51 ug/l, and TPHG and BTEX were not detected. The nearby impoundments might contribute to a small groundwater mound near MWWES-1 however the amount of seepage from the impoundments and possible effects upon the shallow aquifer are not known. It is anticipated that a quarterly monitoring program will continue following the well installation and initial sampling PHS/EHD report review. Wright will schedule the next groundwater sampling event. If the concentrations remain stable or decline at the next sampling, Wright will propose to begin the site closure process. 8.0 Limitations This report has been prepared specifically for the Waste Water Treatment Plant Site at 3900 Holly Drive in Tracy, CA, and was done according to the current State and local agency suggested guidance documents for these investigations. The interpretations, conclusions and recommendations made herein are based on the data and analysis for the soil and water samples collected on-site. Conditions of the property can change over time and the use of this report by third parties is entirely at their own risk. The soil borings/monitoring well/groundwater sampling data can only present information accurately on the area directly at the point of the boring. They give a general indication of the condition of the site, but will not serve as a basis for a guarantee of non-contamination of the site. The conclusions and professional opinions that will be presented are developed in accordance with generally accepted practice as outlined in the guidelines of the California Regional Water Quality Control Board and/or other agencies for soil and groundwater sampling. The chemical analysis results are based on data collected at the sampling locations only, therefore Wright Environmental Services,Inc. cannot have complete knowledge of the underlying conditions. Conditions at the project site will change with time due to natural processes or the works of man. Accordingly, the findings of this report will apply to the present conditions only; the opinions expressed therein are subject to revisions in light of new information, and no warranties are expressed or implied. Page 6 of 9