SITE INFORMATION AND CORRESPONDENCE

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KLE/NFELDER B IpM haple.Right Iolut— • 4s and MW-4d, (located northwest of Basin B) may suggest multiple areas of perched groundwater conditions. This is also consistent with an alluvial and overbank depositional environment. Therefore, channel deposits would be sporadic in their occurrence and generally be within finer grained overbank sediments. • Based upon the historical findings of nested monitoring wells MW-4s and MW-4d, Basin "B" does not appear to contribute to perched water conditions. • It appears the perched water in Monitoring Wells MW-2 and MW-5 does not represent a single continuous perched groundwater in which a groundwater flow direction can be assessed. Therefore, the need'for an additional monitoring well to comply with RWQCB M&RP No. 97-811 to ascertain groundwater gradient does not appear to be appropriate. In an August 17, 1998 proposal, Kleinfelder documented the proposed installation of four monitoring wells in the Barbagelata orchard located to the west across Escalon Bellota Road. The assessment was later requested by Mr. Rudy Schnagl of the State of California Central Valley Regional Water Quality Control Board in a letter dated February 26, 1999 and subsequent correspondence dated May 28, 1999 and September 20, 1999. The proposed scope of work was modified in Kleinfelder's work plan addenda dated July 1, 1999 and August 26, 1999, based on Mr. Schnagl's comments. In October 1999, three groundwater monitoring wells were installed by • Kleinfelder within the Barbagelata orchard south of Potter Creek. The wells were installed to monitor shallow perched groundwater conditions in the area. Additionally, attempts were made to install a shallow groundwater monitoring well north of Potter Creek, which yielded no shallow perched groundwater to a depth of approximately 181/2 feet below grade. Groundwater gradient in the shallow perched aquifer in October 25, 1999, December 27, 1999, March 23, 2000, and April 27, 2000 ranged from 0.002 to 0.004 feet/foot to the south southwest, south, northwest and south-southwest, respectively. Perched groundwater flow in the area of the Potter Creek bridge was not noted flowing towards the north (towards the Eason and Dodge properties). Rather, the shallow perched groundwater flow appeared to be away from Potter Creek and was confirmed by the lack of perched groundwater to a depth of 18-1/2 feet in the Barbagelata's orchard north of Potter Creek. However, in areas of flat groundwater gradients such as this site, groundwater flow directions may significantly fluctuate due to rainfall, groundwater recharge, groundwater pumping, etc. Therefore, changes in groundwater flow directions may vary at this site with time. The results of that well installation were detailed in a report dated June 30, 2000 and included the following conclusions: • 117226.E02/ST012R0696 Page 13 of 43 September 14, 2012 Copyright 2012 Kleinfelder