SITE INFORMATION AND CORRESPONDENCE

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�E/NFELOER �Bright People. 9 olutione. 1 ) At the request of the RWQCB sampling was conducted of available ground and surface water monitoring locations for a detailed suite of chemical analysis . The sampling was conducted on October 3 and 4, 2000. Review of Charts 11a through 11h appears to indicate similar water chemistry for the surface water sample locations and the deep aquifer monitoring wells. Based on the chemistry, it appears that the surface water samples are generally of a better water quality like the deep aquifer and unlike the shallow perched water. Please note that a water sample was not obtainable from surface water sample location S4, which has been suspected to be in connectivity with the shallow perched aquifer in monitoring wells MW5 , MW7, MW8, and MW9. There is a distinctly different water chemistry for the water samples obtained from shallow perched aquifer monitoring wells MW5 and MW7 through MW9 . The water chemistry of monitoring well MW2 is markedly different from all samples . That difference further supports the notion of a lack of connectivity between the shallow perched groundwater at MW2 and MW5/MW7/MW8/MW9 . In summary, Kleinfelder theorizes that based on the chemical analysis conducted that the water present in wells MW5, MW7, MW8 , and MW9 is from a different source than the other water samples analyzed . Also, it is theorized that the shallow perched aquifer does not originate from Basin B on the nursery, which is supported by the consistent lack of water in MW4s and MW4d over the last few years and the consistent shallow perched groundwater gradients coming primarily from Potter Creek (to the northeast) and not the nursery to the east. On March 18, 2002, three dewatering wells were installed at Normans Nursery, along the nursery's northwest boundary east of Escalon Bellota Road and southwest of MW-5 . The dewatering wells were spaced approximately 75 feet apart extending north to south . The three dewatering wells (DW- 1 , DW-2 , and DW-3) were installed to total depths of 20 (DW-2 and DW-3) and 30 feet (DW-1 ) below the ground surface (bgs) . The dewatering wells were made operational during the third quarter of 2002. Discharge from the dewatering wells is directed to Basin B where it undergoes dentrification along with the other tailwater within the basin . Daily and weekly surface water and rainfall monitoring has been ongoing since the MRP was required by the RWQCB in 1997. Quarterly groundwater monitoring of the onsite shallow and deep monitoring wells has also been ongoing since installation ( 1997 and 1999, respectively) in accordance with the MRP. The results of historical groundwater monitoring at the site are summarized in the Tables and Charts section of this report. Based on the monitoring results , the RWQCB has been working on a revised MRP for Norman 's Nursery since 2007. 117226. E02/ST013R0176 Page 17 of 40 January 31 , 2013 Copyright 2013 Kleinfelder