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Mr. Geoffrey Rader Page 2 of 7 Groundwater samples collected during the first quarter of 2019 were analyzed for total petroleum hydrocarbons as gasoline (TPHg) using EPA Method 8015M; for benzene, toluene, ethylbenzene and total xylenes (BTEX) using EPA Method 8260B; and for gasoline oxygenates and additives (tert-butyl alcohol [TBA], methyl tert-butyl ether [MTBE], di-isopropyl ether [DIPE], ethyl tert- butyl ether [ETBE] and tert-amyl methyl ether [TAME]) using EPA Method 8260B. Select groundwater samples were also analyzed for total petroleum hydrocarbons as diesel(TPHd)using EPA Method 8015M. Per the revised MRP the analysis of 1,2-dichloroethane (1,2-DCA) and ethylene dibromide(EDB)is no longer required. No samples were collected from the SVE system. Water Level Monitoring On December 19, 2018, and March 20, 2019, a Ground Zero technician measured the static depth to water in all site monitoring wells. On December 19, 2018, the depth to groundwater ranged from 52.69 feet below top of casing (btc) in well MW12 to 56.04 feet btc in well MW8. Groundwater levels in the shallow zone wells rose by an average of 0.12 feet between September 10,2018,and December 19,2018. The water level in the deeper zone,as measured in well MW 1 D, rose by 0.64 feet during the same period. A slight upward vertical gradient was present between the shallow wells and the deep zone well MW1D during the December 2018 monitoring event. On December 19, 2018, shallow groundwater was interpreted to flow generally in a southerly direction, with a mound of high groundwater elevation around well MW7, at a gradient ranging from approximately 0.02 feet per foot (ft/ft) in the central portion of the site to 0.005 ft/ft in the area to the south of the site. This is generally consistent with historical measurements. On March 20, 2019, the depth to groundwater ranged from 51.47 feet btc in well MW 12 to 55.15 feet btc in well MW8. Groundwater levels in the shallow zone wells rose by an average of 1.16 feet between December 19, 2018, and March 20, 2019. The water level in the deeper zone, as measured in well MW1D, rose by 1.25 feet during the same period. A slight upward vertical gradient was present between the shallow wells and the deep zone well MW 1 D during the March 2019 monitoring event. On March 20, 2019, shallow groundwater was interpreted to flow generally in a southerly to southeasterly direction, with a slight mound of high groundwater elevation around well MW7, at a gradient ranging from approximately 0.02 ft/ft in the central portion of the site to 0.003 ft/ft in the area to the south of the site. This is generally consistent with historical measurements. Potentiometric surface maps for December 19,2018,and March 20,2019,are presented on Figures 3 and 4,respectively. Table 1 contains well construction details based on the limited data available in our files. Groundwater elevation data from the March 2019 monitoring event are presented on Table 2. Historic groundwater elevation data, groundwater flow direction and gradients are summarized in Table 3. Field data sheets for the December 2018 and March 2019 monitoring event are included in Attachment A.