ARCHIVED REPORTS_QUARTERLY REPORT - SECOND QUARTER 2008

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2. METHODS Groundwater samples were collected by Advanced GeoEnvironmental, Inc. on 05 May 2008, for the groundwater recirculation system pre-start up sampling event and by Confluence Environmental, Inc. on 18 June 2008, for the second quarter sampling event. On 05 May 2008, a technician measured water levels and sampled intermediate zone monitoring wells MW-313, MW-413, MW-513, MW-913, MW-1013, and MW-1313. On 18 June 2008, a technician measured water levels for intermediate zone monitoring wells MW-1B through MW-5B, MW-913, MW- 1013, MW-13B and extraction well EW-11B and sampled wells MW-313, MW-513,MW-913,MB- 1 OB and EW-11B. Extraction well EW-11B was sampled from the sampling port of the paired recirculation wells EW-11 B/IW-BH2A at the recirculation system. The groundwater monitoring well system is comprised of 16 wells with a suffix to designate the water bearing zone the wells are screened across. The "A" wells (for example, MW-IA) are screened across a shallow water-bearing zone,the `B"wells (for example, MW-313) are screened across an intermediate water-bearing zone, and one well, MW-3C, is screened across a deep water-bearing zone. Figure 2 illustrates the layout of the well system and Table 7 presents information regarding individual well construction and specifications. The alpha designation indicates the water-bearing zone being monitored. The "A" wells are screened across a shallow water-bearing zone, the `B" wells are screened across an intermediate water-bearing zone, and one well, MW-3C, is screened across a deep water-bearing zone. 2.1 Sampling Procedure Depth to water was measured from the top of each monitoring well casing using an electronic water level indicator accurate to 0.01 foot. The top of each well casing has been surveyed so that groundwater elevations can be calculated relative to mean sea level (MSL). After the technician measured static water levels in the above referenced wells, each well was then purged prior to sample collection. Wells were purged to remove stagnant water from the casing in order to collect groundwater samples representative of aquifer conditions. Purging involved removing three casing volumes of water from each well, unless the well purged dry during pumping. Purging was accomplished utilizing an electric submersible groundwater pump. Measurements of groundwater pH, conductivity, and water temperature were collected and evaluated during purging to ensure that fresh formation water was flowing into the well. Groundwater sampling sheets are presented in Appendix A. A groundwater sample was collected from each well after the water level recovered from purging to at least 80 percent of the pre-purging level, unless the well was slow recharging(< 80 percent recovery within two hours). If the well was slow recharging, a sample was collected as soon as enough water was present in the well to complete sampling. Each sample was collected using a new disposable polyethylene bailer. Samples were transferred from the bailer to laboratory- provided sample containers with a slow-emptying device to minimize turbulence and potential 6