SITE INFORMATION AND CORRESPONDENCE

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KLE/NFELOER P/9Ft FeoOk.PryFtSWUM1on3. • In a March 31, 1999 proposal, Kleinfelder documented the proposed installation of three deep monitoring wells on site. The assessment was 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 late November 1999, three deep groundwater monitoring wells were installed on the property. The results of that work were detailed in Kleinfelder's "Deep Groundwater Assessment, Norman's Nursery,...," dated August 25, 2000. That report stated the following: Based on the information obtained during this assessment as well as the ongoing monitoring of deep groundwater, the shallow perched groundwater and surface water, the following conclusions and recommendations were made. 1) In late November 1999, three deep groundwater monitoring wells were installed within the nursery property. The purpose of the wells was to evaluate groundwater quality of the first aquifer beneath the site at a depth of approx. 150 feet below grade. The reason • for evaluating the deeper groundwater was to evaluate the potential for the nursery to be impacting the drinking water wells on the nearby Dodge and Eason properties north of the nursery. Both properties have production wells with water in the general range of 100 mg/I (parts per million) nitrate as nitrates which is equivalent to approximately 22 mg/I nitrate as nitrogen. The monitoring wells have been developed, surveyed, purged, sampled and monitored. The monitoring dates for said deep groundwater (DP-1 through DP-3) were monitored on December 28, 1999, March 21, 2000, April 26, 2000, May 22, 2000, and June 21, 2000. Quarterly reports have been issued documenting those findings. In general, groundwater flow on all five monitoring events was consistently calculated to be 0.003 feet/foot to the southwest. This flow direction matches the San Joaquin County Flood Control and Water Conservation District data detailed in Section 2.4.4 of this report. Please note that these monitoring events took place during the winter when the nursery was not irrigating and during the spring and summer when they were irrigating. According to the nursery's water use records, the nursery did not irrigate from November 21, 1999 to late-March 2000. Therefore, the gradient and flow direction for groundwater within the deep aquifer appears to be consistent irrespective of pumping. No obvious impact of the nursery's operations on deep groundwater quality. Additionally, the direction of groundwater flow in the deep aquifer is towards the southwest and not towards the Dodge and Eason wells to the north. Based on the results of the monitoring conducted, published information and the conclusions outlined above, the following recommendations were made by Kleinfelder: • 117226.E02/ST012R0696 Page 15 of 43 September 14, 2012 Copyright 2012 Kleinfelder