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Monitoring Report Compliance Checkli 5 <br /> a <br /> Discharges Regulated by Title 27 and/or Part 258 <br /> 21. VOCs have been detected in all gas wells associated with vadose zone monitoring. Methane has been detected in gas <br /> well GW-6. <br /> 2.m. Well MW-5 continues to show measurable evidence of a release of VOCs to groundwater as indicated by the retest <br /> data presented as the 3`d quarter report. During the 2"d Quarter and 3`d Quarter of 2006, 7 and 9 VOCs were detected, <br /> respectively. In the 2nd quarter report there were four VOCs with increasing trends and in the 3`d quarter report there were <br /> three increasing trends. TDS and chloride have been reported as increasing in well MW-5, which could indicate leachate <br /> is impacting groundwater. Per Title 27, section 20385(a)(2),the Dishcarger is required to institute an Evaluation <br /> Monitoring Program (EMP)under section 20425. <br /> 2.0. Well MW-5 top of screen interval is set at an elevation of 229' msl. GWE have been recorded over the last six events <br /> ranging between 231.79 and 236.13 feet above msl. Since well MW-5 continues to have detectable VOCs, several of <br /> which have increasing trends, staff is concerned whether the well is being purged sufficiently to collect a representative <br /> sample of formation water. According to the field data sheets,the difference between the static DTW measurement and <br /> the DTW measurement following sampling is only 0.62'. DTW levels between end of purge and sampling were not <br /> recorded. The GWE for MW-5 in the third quarter was 235.77 feet above msl. The 0.62' drawdown recorded during the <br /> third quarter would result in a GWE of 235.15 feet above msl. This would result in DTW approximately 6.15 ` above the <br /> top of screen. It is unclear if groundwater samples collected are coming from the screened portion of the well that <br /> communicates with the shallow aquifer. Staff recommends the Discharger evaluate the purge and sampling of well MW-5 <br /> to determine whether formation water is being collected. If the recharge rate in the well does not allow for proper <br /> drawdown,then the Discharger must propose an alternative method to ensure formation water is being brought into the <br /> well and sampled. Wells MW-6 and MW-7 also have GWE above the top of screen intervals. <br /> RWQCB Staff Signature: !� J <br /> Date: Q� <br />