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Ms. Kristin Shelton
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<br /> August 14, 2013, and it operated until November 18, 2013, when it was discovered that two of the
<br /> t three heating element banks burned out. The system was re-wired to operate on the third heating
<br /> element bank and was restarted on November 20, 2013. The system operated from November 20,
<br /> 2013, to January 3, 2014, when the system was down upon arrival of the technician and would not
<br /> ' heat up properly upon restart. The SVE system remained non-operational from January 3, 2014, to
<br /> December 12, 2014. On December 12, 2014, a new, custom-fabricated, heating element was
<br /> installed and the SVE system was restarted. On April 10, 2015, the SVE system was modified to
<br /> extract only from extraction well VEWl-D (previously the SVE system extracted from wells
<br /> VEW1-S, VEWl-I and VEWI-D), as a targeted effort to eliminate the presence of free floating
<br /> hydrocarbon product from the site. The system currently remains operational.
<br /> Since system startup on August 29, 2012, through December 30, 2015,the SVE system has been
<br /> monitored on a monthly basis (except when the system was down for extended periods of time
<br /> for repairs). During this period, the system operated for approximately 16,560 hours, extracting
<br /> approximately 15,750 pounds of hydrocarbon vapors from the subsurface. Influent and effluent
<br /> ' vapor concentrations were monitored monthly using a photoionization detector (PID). During
<br /> the year 2015 influent soil vapor samples were collected on a monthly basis: soil vapor sampling
<br /> events occurred on January 29, March 17, April 20, May 18, June 15, July 9, August 13,
<br /> September 10, October 8, November 12 and December 30, 2015. The soil vapor samples were
<br /> collected into Tedlar bags and delivered, under chain-of-custody protocol, to the laboratory for
<br /> analysis.
<br /> The location of the SVE system, the equipment compound and the extraction wells are shown on
<br /> Figure 2 (Attachment A). Vapor extraction system monitoring and hydrocarbon mass removal
<br /> ' data have been summarized on Table 7 and soil vapor laboratory analytical data has been
<br /> summarized in Table 8 (Attachment B). Results for the first half of 2015 were reported in
<br /> Ground Zero's Semi-Annual Groundwater Sampling and Remediation Status Report, dated July
<br /> ' 15, 2015, and results for the second half of 2015 were reported in the Semi-Annual Groundwater
<br /> Sampling and Remediation Status Report, dated January 21, 2016.
<br /> ' GROUNDWATER MONITORING AND ANALYTICAL RESULTS
<br /> First Quarter 2015
<br /> On March 12, 2015, shallow groundwater was interpreted to flow in a southerly to southeasterly
<br /> ' direction, with a slight mound of high groundwater elevation around well MW8, at a gradient
<br /> ranging from approximately 0.006 ft/ft in the area south of the site to 0.017 ft/ft in the central and
<br /> southern portions of the site. Figure 3 in Attachment A depicts the potentiometric surface on
<br /> March 12, 2015.
<br /> On March 12 and 13, 2015, groundwater samples were collected from wells MW 3, MW5,
<br /> ' MW6R, MW8, MW11, MW12, MW13, MW14 and MW1D for analysis. Wells MW2, MW4
<br /> and MW 10 are sampled semi-annually during the second and fourth quarters of the year; well
<br /> MW7 was not sampled because the well was dry; well MW9R was not sampled due to the
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<br /> G1DatatGROUNDZE\WOOLSEY.ROB\ReponstQMR\2015 QMRAANNUAL REPORTWiml Textjw.doc
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