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w w from Duck Creek, it cannot be assumed that the water chemistry is the same as water in the aquifer upgradient of the Site. MW-5 has also been used to evaluate potential lateral migration from the Site to Duck Creek. However, semi-annual monitoring events under the WDR require collection of three surface water samples from Duck Creek, as described in the Sample Collection and Analysis Plan. These samples will more accurately represent data from Duck Creek that a sample from MW-5; therefore, it will not be necessary to continue monitoring activities at MW-5 for this purpose. Given that MW-5 accesses water that is not present at the other monitoring well locations, combined with the potential for it to be influenced by lateral migration from Duck Creek, MW-5 is not appropriate for use in the monitoring well network as a background monitoring point and is recommended for removal. 3.2 MONITORING WELL MW-6 Monitoring Well MW-6 is located on the south side of the landfill and is 53 feet deep. Drill data collected during the installation of MW-2A, MW-3A, and MW-9A (Clayton, 2007), indicated that saturated conditions were encountered at a depth of approximately 60 feet bgs. This discrepancy suggests that MW-6 may either access water stranded within the landfill, influence from Duck Creek, or a combination of both. Based on this information, MW-6 is probably not appropriate for comparison to the other wells in the network and it is questionable whether water in this well is groundwater or a combination of groundwater and surface water. MW-6 is recommended for removal. 3.3 MONITORING WELLS MW-7 AND MW-8 Monitoring wells MW-7 and MW-8 are located on the northwest corner of the landfill. MW-7 is completed to approximately 43 bgs and MW-8 is completed to roughly 61 feet bgs. MW-7 was completed to a similar depth as MW-2, MW-3, and MW-9,which were removed. MW- 7 is not appropriate for use as an upgradient well because it does not access the same water bearing zone as the new down gradient wells (MW-2A and MW-3A). MW-7 is recommended for removal. MW-8 likely accesses the same water bearing unit as MW-2A, MW-3A, and MW-9A; however, because it was only drilled to 61 feet bgs, its screened interval is adjacent to the finer-grained sediment of the confining unit, rather than the coarser-grained sediment of the aquifer. An appropriately constructed well that accesses the same zone as the other wells will provide a better basis for comparison. In addition, previous groundwater investigations have indicated that MW-8 is more likely a perimeter cross gradient well than a true upgradient monitoring well. Based on this information MW-8 is also recommended for removal. 4 AWFLL R MMOOKAW P:\707 Cove Contractors\WDR\Tech Report and WP 2008\Tech Report and WP_FINAI.doc