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Bank of Stockton page 2 <br />' WiLnter 1996 Quarterly Momtormg Report <br /> Project No 358 2 <br /> Apn18,19% <br />' ft/ft, flowing North 46' East (Figure 2) Except for the depth to groundwater, <br /> this data compares favorably to the previous monitoring events in that the <br /> groundwater flow is generally northeast (Table 1 Appendix A). <br /> 1.2 Groundwater Sampling <br /> On March 28, 1996, depth to all five moFutormg wells was checked and four of <br /> the monitoring wells were purged and groundwater samples were collected <br /> Samples were collected in the following order, MW-2, MW-3, MW-4 and MW-1. <br />' Groundwater quality parameters were recorded while purging the wells and are <br /> tabulated in the groundwater monitoring field notes (Appendix C). An unused <br /> domestic water well, herein designated DW-1 was not sampled, nor was MW-5 <br />' 1.3 Groundwater Sampling Procedure <br />' On March 28, 1996, Del-Tech GeotechYucal Support personnel and Geological <br /> Technics Personnel arrived on-site, opened the wells, and measured the depth to <br /> water with an electrically actuated sounding tape. The water level reading was <br /> recorded to an accuracy of 0.01 foot. In wells where free floating product was <br /> suspected, a clear disposable bailer was used to gauge the interface No floating <br /> I product was observed during this sampling event. All wells except MW-1 were <br /> found to have 2 to 4 feet of sediment in the bottoms of the casing. <br /> Stagnant water in the well casing was purged using a stainless steel bailer <br /> belayed with a servo actuated electric reel The rate of well purging was <br /> monitored. The bailer was also used to help surge the well in order to dislodge <br /> the sediment in them. Each well was purged of at least three casing volumes <br /> and then purged until the groundwater parameters (temperature, conductivity, <br /> and pl-1) had stabilized (Appendix C.) indicating that water, representative of <br /> actual aquifer conditions, was entering the well Groundwater parameter <br /> stabilization was characterized by three successive readings within 10`Yo <br /> Before a sample was collected, the well's water level was allowed to recharge to <br /> at least 80% of it's initial level All water removed from each monitoring well <br /> and not used as a sample, was placed in a 55 gallon DOT (Department of <br /> Transportation 17-H) approved container that is properly labeled and <br /> temporally stored on-site <br /> A bailer was used to collect each sample Bailer cleanliness was assured by <br /> collecting a bailer blank (pounng distilled water through the bailer and <br />