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Quarterly Monitoring Report—Fourth Quarter of 2009 Page 3 TURNER ROAD VINTNERS January 22,2010 WKA No. 5279.03 _ There are five groundwater-monitoring wells split between the two facilities. Four of the five monitoring wells (MW 1, MW2, MW4, and MW5) are located proximal to the wastewater treatment ponds on the West Facility. The remaining monitoring well (MW3) is located on the East Facility. Three groundwater-monitoring wells (MW 1 through MW3) were installed in September 1999 by NOA Environmental pursuant to RWQCB MRP No. 99-103 requirements. Wallace-Kuhl and Associates, Inc. (WKA) installed two additional monitoring wells(MW4 and MW5) in August 2004. Topography in the vicinity of the site is relatively flat, with elevations decreasing gradually from east to west. According to the USGS Thomton 7.5-minute topographic quadrangle (1968, revised 1993), the East Facility has surface elevations of approximately 20 to 25 feet above mean sea level (msl) while the West Facility has surface elevations of approximately 10 to 18 feet above msl. 4.0 MONITORING AND SAMPLING The groundwater monitoring well network at the Winery consists of the five monitoring wells discussed above (Figure 2). The surveyed top-of-casing elevations are presented in Table 1. The survey data presented in Table 1 is based on a horizontal and vertical control survey conducted by Morrow Surveying, Inc. of West Sacramento, California. The coordinates are referenced to the California State Plane Zone 3 coordinates from global positioning satellite (GPS) observations using University of California Bay Area Deformation CORS station observation files referenced on the California Spatial Reference Center Datum, Epoch 2000.35. The vertical datum used for elevation determination is based on NAVD88 from GPS observations. 4.1 Groundwater Monitoring On December 29 and 30, 2009, WKA conducted fourth quarter groundwater monitoring and sampling at the site. Monitoring consisted of measuring DTW in each well. DTW measurements were obtained with an electronic sounder with a tape graduated in 1/100ths of a foot. DTW measurements were obtained to an accuracy of+0.01 feet. DTW was recorded in each monitoring well from the top-of-casing (north side). Groundwater equipotential elevation contours, calculated groundwater elevations in monitoring wells, and apparent direction of groundwater flow on the date of monitoring are illustrated in Figure 3. Table 2 includes DTW and calculated groundwater elevations obtained from this monitoring event. Table 2 also includes a compilation of historical DTW and groundwater elevations based on the recent survey _ results. Groundwater elevations are presented in feet above mean sea level (msl).