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4.0 Monitoring Well Gauging and Sampling Monitoring wells were initially sampled as soon after well development as possible. Wells MW-2 and MW-4 were initially sampled on January 6,2005. These wells were purged to dryness using a variable speed electric submersible pump several times until 3 wetted casing volumes of water had been removed. Groundwater samples were then collected from the pump discharge line. Wells MW-1 and MW-3 could not be developed and initially sampled on January 6th due to equipment and well development problems. Wells MW-1 and MW-3 were initially sampled on January 25, 2005 approximately one week after development was complete. At MW-1 and MW-3, a new disposable bailer was used to purge the wells to dryness once, and samples were then collected when water had sufficiently recharged in the well for sampling. The results of initial well gauging and sampling are presented in the following sections. A quarterly groundwater sampling program for the four wells is to be initiated at the site beginning • no later than March 31, 2005. Due to the low yield conditions of all four wells and the relatively small volume of water in each well, a disposable bailer will most likely be used for purging and sampling each well in the future. It is anticipated that each well will be purged to dryness once, then allowed to recover prior to sampling. 4.1 Results of Well Gauging All four wells were gauged for depth to water and total depth on January 6°i and 24th,2005. Table 2 is a summary of well gauging data available for the site. Table 2 shows that groundwater occurs at between 106 and 109 feet BGL at an elevation between-38.0 and-41.0 feet. The January 6th gauging results at MW-3 were deemed to be non-representative of the upper most aquifer due to an obviously anomalous groundwater elevation value of-3.0 feet. The cause for this anomalous reading is addressed in Section 3.0 of this report. Additionally, all depth to water gauging results prior to well development are considered suspect. Consequently,for the currently available gauging data,the gauging results collected on January 24th are deemed to be the only representative data available at this time. • 6