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Site Background Information AGE Project No. 13-2557 Page 4 of 4 AdvancedGeo Fnvironmental ggg concentrations of 620 pg/I (B1). Tetrachloroethene (PCE) was detected in shallow groundwater samples collected from B4, B6, and B7 at a maximum concentration of 0.91 pg/I (B4). Dissolved lead (Pb) was detected in the shallow groundwater sample collected from B3 at a concentration of 4.3 pg/I. Lead was also analyzed in the samples collected from B4 and B8 and was not detected above the laboratory detection limit (<0.5). TPH-g were detected in deep groundwater samples collected from borings B2 and B4 at concentrations of 910 pg/I in B2 and 87 pg/I in B4. BTEX compounds were detected in deep groundwater samples collected from B2 and B4, except for benzene in B4, at maximum concentrations of 0.72 pg/I benzene, 6.0 pg/I toluene, 2.3 pg/I ethylbenzene, and 6.9 pg/I total xylenes (B2). Naphthalene was detected in deep groundwater samples collected from B2 and B6 at concentrations of 3.4 pg/I and 0.56 pg/I, respectively. POE was detected in all four deep groundwater samples collected from B2, B4, B6, and B8 at a maximum concentration of 2.5 pg/I (B6). Trichloroethene (TOE) was detected in the deep groundwater sample collected from B6 at a concentration of 0.51 pg/I. Dissolved Pb was not detected above laboratory reporting limits in the deep groundwater samples collected from borings B2, B4, B6, and B8. Analytical results of grab groundwater samples are summarized in Table 2 and the estimated lateral distribution of dissolved TPH-g, benzene, and naphthalene are depicted in Figures 4, 5, and 6. Based on the data collected during the May 2017 investigation, the lateral extent of petroleum hydrocarbon-impacted soil is defined to the west, north and east by borings B1, B4 and B6; and is undefined toward the south beyond boring B5 and toward the northwest beyond boring B2. The vertical extent of petroleum hydrocarbon-impacted soil is defined and does not extend to 20 feet bsg in the former UST area (B3) or in the locations of the remaining borings (Figure 3). The lateral extent of dissolved TPH-g is defined to the east and northeast by borings B4 and B6, but is undefined in the remaining directions (Figure 4); dissolved benzene and naphthalene are defined to the east, north, northeast, and south by borings B4 through B8, but are undefined to the west and northwest in the presumed down-gradient direction from the former UST area (Figures 5 and 6). However, based on data collected from the site assessment at 95 West 11th Street (T0607742311), dissolved petroleum hydrocarbons do not extend to the west in the locations of former wells MW-7 and MW- 12. The vertical extent of petroleum hydrocarbon-impacted groundwater is undefined to the northwest in the presumed down-gradient direction from the former UST area (Figures 5 and 6). However, low concentrations of BTEX compounds detected in the deep grab groundwater sample collected from boring B2 suggests that impacted groundwater does not extend much further than 40 feet bsg.