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' 20 March 2015 <br /> AGE Project No. 00-0769 <br /> ' Page 4 of 19 <br /> ' JUNE 2014 <br /> On 03 June 2014, a progress-pilot test monthly monitoring and sampling event was <br /> ' performed utilizing wells MW-1, MW-2A, MW-3A, MW-5A, MW-6B, MW-7B, MW-8A, <br /> MW-9A, and MW-10 as required by the MRP; depth to groundwater was measured; pH, <br /> EC, and temperature were measured during well purging and final values after purging <br /> ' was complete were utilized; DO and ORP were measured down-hole prior to purging in <br /> non-CMT wells and from purge water during the initial purge volume in CMT wells; and <br /> groundwater samples were collected in each of the above-mentioned wells. <br /> ' Groundwater samples were analyzed for the constituents required in the MRP <br /> (Appendix B). <br /> ' • Depths to groundwater ranged between 19.50 feet (MW-8A) below the tops of <br /> the well casings (btoc) and 21.90 feet (MW-1) btoc (Table 1). Groundwater <br /> elevations at the site ranged between 7.92 feet (MW-10) below North American <br /> ' Vertical Datum 88 (NAVD88) and 11.24 feet (MW-1) below NAVD88. <br /> • Total petroleum hydrocarbons quantified as gasoline (TPH-g) were detected in <br /> groundwater samples collected from wells MW-1, MW-2A, MW-3A, MW-5A, <br /> ' MW-6B, MW-7B, and MW-10 at concentrations ranging from of 630 micrograms <br /> per liter (pg/1) in MW-2A to 230,000 pg/l in MW-1. Benzene, toluene, <br /> ethylbenzene, and total xylenes (BTEX) were detected in groundwater samples <br /> ' collected from all nine wells sampled at maximum concentrations of 19,000 pg/l <br /> benzene, 79,000 pg/l toluene, 4,300 pg/l ethylbenzene, and 29,900 pg/l total <br /> xylenes (Table 2). <br /> ' pH was measured between 6.91 and 7.43; EC was measured between 543 and <br /> 1,395 microSiemens per centimeter (pS/cm); temperature was measured <br /> ' between 19.8 and 24.8 degrees Celsius; DO was measured between 0.63 and <br /> 4.96 milligrams per liter (mg/I); and ORP was measured between -318.2 and - <br /> 261.1 millivolts (mV). Results of YSI Multi-Parameter Meter data is presented in <br /> ' Table 3. <br /> • Various dissolved metals (barium [Ba], boron [B], aluminum [Al], calcium [Ca], <br /> t iron [Fe], potassium [K], magnesium [Mg], manganese [Mn], sodium [Na], and <br /> zinc [Zn]) were detected in groundwater samples collected in June 2014. <br /> Concentrations of Ba detected in samples collected from wells MW-1, MW-2A, <br /> ' and MW-5A and concentrations of Al detected in MW-9A were above their <br /> respective State of California Primary Maximum Contaminant Levels (MCLs) for <br /> drinking water; concentrations of Ba and Al detected in the remaining samples <br /> ' were below their respective MCLs; and concentrations of Fe and Mn detected <br /> were significantly above the State of California Secondary MCLs for drinking <br /> water. Concentrations of Ca, B, Mg, Na, K, and Zn all appear to be within normal <br /> ' background levels. Analytical results of metals are summarized in Table 4. <br /> • Hexavalent chromium was not detected above the laboratory reporting limit <br /> (0.2 pg/1) in groundwater samples collected in June 2014 (Table 4). <br /> Advanced GeoEnviron mental Inc. <br /> 1 <br />