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the documented well construction problems at MW-3,a significant concern over well integrity becomes warranted. 5.0 Discussion,Summary,and Conclusions It should be noted that the results of a single round of sampling results do not necessarily constitute a reliable indication of groundwater conditions. It is well documented that constituent concentrations in groundwater fluctuate with seasonal changes and that there are inherent uncertainties introduced during sample collection and laboratory analysis. In fact,USEPA standard methodology requires that a minimum of 16 independent groundwater samples be collected(usually as quarterly samples from 4 wells during a period of one year) and statistical analysis be conducted before any legally defensible conclusions regarding groundwater quality can be established. The direction of groundwater flow is indicated to be toward the west, and MW-3 is located immediately south of the wastewater pond. It could be suggested that MW-3 does not represent down-gradient groundwater conditions from the wastewater pond. However, it is contended that any seepage from the waste water pond,while traveling 100 feet down to the groundwater table, would necessarily be dispersed such that well MW-3 can be considered to be directly beneath the wastewater pond from a hydrogeologic perspective. Additionally,published maps of groundwater elevation from the San Joaquin County Flood Control and Water Conservation District indicate that the site is situated near a groundwater divide and that groundwater flow has been toward the south at different times during recent years. This situation indicates that the direction of groundwater flow in the area is variable and that MW-3 and MW-4 may be directly down-gradient of the wastewater pond at certain times during the season. The variable direction of groundwater flow in the area may, in part,be the result of production well withdrawal. Well construction at MW-3 encountered problems which ultimately raise questions concerning well integrity. Samples from the well display unusually high pH and specific conductance, and the silt accumulates in the well at an excessive rate. Replacement of MW-3 with a new well should be considered. 8