SITE INFORMATION AND CORRESPONDENCE

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KLENFELOER /a, hpfe. Rightwwor,. 5 . According to the Spring 2008 Groundwater Report by the San Joaquin Flood Control and Water Conservation District, groundwater beneath the Norman 's Nursery site exists at a depth of approximately 140 to 150 feet (elevation of -20 feet msl ) and flows towards the south-southwest. According to the U . S . D.A. soil survey, perched water conditions may exist in the area . Perched water conditions were encountered by Kleinfelder during the installation of Monitoring Well MW-2 and in Monitoring Well MW-5. Perched groundwater was also encountered during excavation of 4 of the 10 test pits across the site in November 1998 . In general , the perched water was noted in the northwest and southeast portions of the site . Perched water at these locations was noted between the depths of 2'/2 to 9 feet bgs (primarily within and above a gravel stratum) in both borings and three of four test pits. Perched water was not apparently located in a single stratigraphic body. 6 . In the past, Kleinfelder has conducted subsurface exploration of the property. This exploration has revealed that soil beneath the site can be generally summarized as clayey gravels . Up to a depth of approximately 17 feet, the clayey gravel contains inconsistent layers of sandy clay or clayey sand that are generally around two feet in thickness. The clayey gravel is generally underlain by a layer of silt or clayey silt approximately 5 to 10 feet in thickness. The silt layer is underlain by silty sand that may contain interbedded layers of clay or clayey silt. 7. Past data suggest that the area around the Escalon Bellota Road Bridge of Potter Creek connects with the shallow perched groundwater in that immediate area . If the two are in connection with one another, then water quality in the area of MW-5 could be influenced by the water quality within that area of Potter Creek. It is unknown if Potter Creek is a gaining or loosing stream in that area. Past water flow estimates of Potter Creek, conducted as a part of the Nursery's monitoring, have yielded discrepancies in the creek's flow in that area. Due to the consistent, historical lack of perched water in wells MW-4s and MW-4d , however, it appears that the area in which Potter Creek connects with the shallow perched groundwater is limited . This indicates that Potter Creek may, at times, be a significant source of the water in the shallow perched groundwater zone . Given the rerouting of Potter Creek to the north following Location S-4, a significant amount of water in the shallow perched groundwater zone would exist in the Barbagelata orchard to the west of Norman's Nursery and Escalon Bellota Road . 117226 .E02/ST013R0176 - Page 34 of 40 January 31 , 2013 Copyright 2013 Kleinfelder