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Ms. Kristin Shelton Page 6 of 10 concentrations of 6,200 ppb and 600 ppb, respectively. Moderate to high levels of toluene, ' ethylbenzene and xylenes were also detected. TPHd was detected in the sample from MW6R at a concentration of 11,000 ppb. TPHg and benzene were detected in the sample from well MW8 at concentrations of 24,000 ppb and 21,000 ppb, respectively. Moderate to high levels of toluene, ethylbenzene and xylenes were also detected. TPHd was detected in the sample from well MW8 at a concentration of 760 ppb. TPHg and benzene were detected in the sample from well MW13 at concentrations of 540 ppb and 42 ppb, respectively. Low levels of toluene, ' ethylbenzene and xylenes were also detected. MTBE was detected in well MW3 at a concentration of 5.2 ppb, in well MW6R at a ' concentration of 4,400 ppb, in well MW8 at a concentration of 34,000 ppb and in well MW13 at a concentration of 8.3 ppb. No other gasoline oxygenates or additives were detected in any site well. Results were reported in the Semi-Annual Groundwater Sampling and Remediation Status ' Report, dated July 15, 2015. ' Groundwater analytical results for the second quarter of 2015 are presented in Table 10 and cumulative analytical results are summarized in Tables 13 and 14 (Attachment B). Isoconcentration maps for TPHg, TPHd, benzene and MTBE are depicted on Figures 9, 10, 11 ' and 12 in Attachment A. Third Quarter 2015 rOn September 9, 2015, shallow groundwater was interpreted to flow in a southerly to southeasterly direction, with a mound of high groundwater elevation around well MW8, at a ' gradient ranging from approximately 0.0 18 ft/ft in the central and southern portions of the site to 0.007 ft/ft in the area to the south of the site (Figure 13 in Attachment A). ' On September 9 and 10, 2015, groundwater samples were collected from wells MW3, MW5, MW8, MW11, MW12, MW13, MW14 and MW1D for analysis. Wells MW2, MW4 and MW10 are sampled semi-annually during the second and fourth quarters of the year; wells MW6R and t MW9R were not sampled due to the presence of free floating hydrocarbon product; well MW7 was not sampled because the well was dry; and well VEW 1-D was not sampled because the well was actively being used for soil vapor extraction. No analytes were detected in the samples collected from wells MW5, MWII, MW12, MW14 and MW1D. TPHg and benzene were detected in the sample collected from well MW3 at ' concentrations of 220 ppb and 4.1 ppb, respectively. Low levels of ethylbenzene and xylenes were also present. TPHg and benzene were detected in the sample collected from well MW8 at concentrations of 44,000 ppb and 10,000 ppb, respectively. Moderate levels of ethylbenzene and xylenes were also present. TPHd was not detected in well MW8. TPHg and benzene were detected in the sample from well MW13 at concentrations of 81 ppb and 3.4 ppb, respectively. A low level of ethylbenzene was also present. MTBE was reported in well MW3 at a concentration of 2.7 ppb,in well MW8 at a concentration of 22,000 ppb and in well MW 13 at a concentration of 29 ppb. No other gasoline oxygenates or G:\Data\OROUNDZE\WOOLSEY.ROB\Repom\QMR\2015 QMRs\ANNUAL REPORTTinal Textjw.doc