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Mr Harlin Knoll Environmental <br /> 9 November 2000 Resources <br /> Page 2 Management <br /> i <br /> Monitoring Well Installation <br /> The monitoring well installation activities were conducted on 19 <br /> September 2000 The location of the new monitoring wells is shown in <br /> Figures 1 and 2 As shown, one monitoring well (MW-7) was installed <br /> adjacent to existing, shallow monitoring well MW-4 at former tank <br /> location 1 The second monitoring well (MW-8) was installed adjacent to <br /> existing, shallow monitoring well MW-6 at former tank location 2 <br /> Consistent with the County's correspondence, these locations are <br /> downgradient of the former tank locations, in the areas where the highest <br /> chemical concentrations have been detected in shallow ground water <br /> Each of the monitoring wells was constructed of 2-inch PVC MW-7 was <br /> screened from 29 25 to 39 25 feet bgs and MW-8 was screened from 29 to <br /> 39 feet bgs The wells were constructed in accordance with all applicable <br /> regulations Soil samples were collected during the installation of each <br /> well for lltholognc interpretation according to the uniform soil <br /> classification system, however, no soil samples were collected for <br /> . laboratory analysis Soil boring logs and well construction logs for these <br /> two wells are included as Attachment A to this letter <br /> Following installation, the monitoring wells were developed on 21 <br /> September 2000 The well development records are included in <br /> Attachment B to this letter <br /> Monitoring Well Sampling <br /> Ground water samples were collected from the two new monitoring <br /> wells and five of the six shallow monitoring wells at the site during the a <br /> sampling event conducted on 3 October 2000 A ground water sample <br /> was not obtained from monitoring well MW-1 during this sampling <br /> event due to damage to the well cover at this location The cover for this <br /> well could not be opened to collect a sample because the bolts on the well <br /> cover had been crushed ERM subsequently replaced the well cover and <br /> collected a ground water sample from MW-1 on 31 October 2000 <br /> In accordance with the workplan, the ground water samples were <br /> analyzed for total petroleum hydrocarbons as gasoline (USEPA Method <br /> 8015), and benzene, toluene, ethylbenzene, and xylenes (USEPA Method <br /> 8020) The ground water sampling analytical results for the current and <br /> historical sampling events are summarized in Tables 1 and 2 Ground <br /> water elevation measurements collected during the sampling event are <br />