SITE INFORMATION AND CORRESPONDENCE

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E KLE/NFELOER • A. Given the deep aquifer groundwater quality before and during Norman's Nursery's growing season and pumping, the nursery appears to have no effect on the elevated nitrate concentrations in the Dodge and Eason wells. The concentrations of nitrate in the nearby wells are generally 3 to 5 times the concentrations of nitrates on the northern edge of the nursery. Furthermore, water flow direction has consistently been to the southwest and not towards the north-northwest. Therefore, other potential sources for the elevated nitrates in the production wells on the Dodge and Eason property should be explored by the RWQCB. These may include fertilization on the adjacent properties, contamination of the water supply by nearby nitrate sources (e.g. septic systems and leachfields), wells with poor surface seals which may allow surface water infiltration, etc. B. Kleinfelder recommends that a copy of this report be submitted to the RWQCB and PHS/EHD for their review and comment. For a summary of the monitoring well construction details for the wells installed at Norman's Nursery and the surrounding property, please refer to Table 6. At the request of the RWQCB, additional chemical analysis was conducted on nearly all available sample locations during the Fourth Quarter of 2000. Those analyses were summarized along with the normal quarterly monitoring data in Kleinfelder's report titled "Fourth Quarter 2000 Ground and Surface Water Monitoring..." dated January 29, • 2001. The following additional special conclusion was made: 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- 11 7226.EO2/ST012RO696 W-117226.E02/ST012R0696 Page 16 of 43 September 14, 2012 Copyright 2012 Kleinfelder