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The groundwater elevation data obtained on November 7,2013 were used to generate the groundwater elevation contour map shown on Figure 2-1 for the fourth quarter 2013 monitoring period, which indicates that groundwater beneath the southern and central portions of the Forward Unit generally flows to the north and northeast at a hydraulic gradient of 0.003 ft/ft, while groundwater beneath the northeast corner of the Forward Unit flows to the southwest at a hydraulic gradient of 0.026 ft/ft. This southwest gradient was first noted during the May 2011 monitoring event and is believed to be related to groundwater mounding, as a result of agricultural activities east of the site. To calculate the approximate linear groundwater flow velocity for the Forward Unit, conservative assumptions were used, including a hydraulic conductivity of 875 gallons per day per square foot(0.04 cm/sec) and an estimated effective porosity of 35 percent (CH2M Hill 2000). An estimated groundwater flow velocity was calculated using Darcy's Law: Ki cm 0.003 sec— ft V = —_ [(0.04—)* ]*2835 = 0.972 ft/day ne sec 0.35 cm —day where: V=Groundwater now velocity. K=Hydraulic conductivity of the water-bearing unit(0.04 cm/sec). i=Hydraulic gradient:i=0.003 to 0.026 for the site during the fourth quarter 2013. ne=Effective porosity(ne=0.35);an estimated value. The maximum groundwater flow rate is calculated to be 0.972 feet per day(355 feet/year)to the north and northeast and 8.4 feet/day (3,075 feet/year)to the southest. Detection Monitoring Program Field and laboratory results for the Forward Unit groundwater monitoring wells for the fourth quarter 2013 monitoring period are summarized in Table 2-2. Non-Statistical Data Anal The non-statistical VOC Water analysis was performed on the DMP well data during the fourth quarter 2013. Review of the analytical data indicates that there is no non- statistical indication of release. During the monitoring period,only one estimated trace concentration of a VOC (dichlorodifluoromethane [DCDFM] at well MW-10)was measured in the samples collected from the Forward Unit. On behalf of Forward Inc., GLA prepared a letter report dated February 14, 2001 (RWQCB Case No. 2209),to assess the source and potential impacts of low-level VOCs in groundwater adjacent to the Forward Landfill. The letter report concluded that the sporadic detection of low-level VOCs in groundwater (and lysimeter samples) at the Forward Unit are most likely due to landfill gas from unlined unit WMU-B. Forward has continued to minimize gas related impacts to groundwater by limiting interim fill areas that promote ponding of water. Furthermore, C:U013-M1\FA_4Q13.dm 5 Geo-Logic Associates