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! In August 2000, JPCA advanced three soil borings 131, MW4, and MW5. The latter two wells
<br /> were completed as monitoring wells. Soil boring B1 was advanced to a depth of 115 feet bgs and
<br /> wells MW4 and MW5 were installed to a depth of 75 feet bgs. Soil and groundwater samples
<br /> ! were collected and analyzed. Site activities were summarized in JPCA's 2nd Phase H
<br /> Environmental Assessment Report, dated October 25, 2000.
<br /> ' In January 2003, GHH Engineering, Inc. (GHH) advanced three cone penetrometer borings and
<br /> three soil borings to depths ranging from 104 feet bgs to 122 feet bgs.
<br /> ' In May 2003, GHH advanced four soil borings, MW6a, MW6b, MW7a, and MW7b to the east of
<br /> the site. These borings were completed as well clusters with MW6 and MW7a advanced to a
<br /> depth of approximately 75 feet bgs, and MW6b and MW7b advanced to a depth of
<br /> ! approximately 94 feet bgs. GHH also installed well EW1 in the southeast portion of the site.
<br /> Site activities were summarized in GHH's Second Quarter 2003 Groundwater Monitoring
<br /> Report and Additional Assessment Report, dated June 2003.
<br /> In January 2004, an ATC geologist supervised the installation of five injection wells (IW1
<br /> IW5) associated with an ozone injection system. Each injection well has a shallow and deep
<br /> spargepoint for the ozone. The shallow spargepoints were installed to a depth of approximately
<br /> 74.0 feet bgs and the deep spargepoints were installed at a depth of approximately 107.7 feet bgs.
<br /> From February 17 to approximately April 20, 2004, an ATC geologist supervised the installation
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<br /> of groundwater monitoring wells MW6c, MW7c, MW8, MW9a, MW9b, MW9c, MW10a,
<br /> ' MW10b, and MW10c. The data for the well installation will be submitted separately in an
<br /> ATC's report entitled Summary Report of Subsurface Investigation.
<br /> ' 2.0 GROUNDWATER MONITORING ACTIVITIES
<br /> On July 16, 2004 and on August 13, 2004 ATC personnel collected groundwater samples from
<br /> ' monitoring wells MW1, MW2, MW4, MW8 and EW 1. On September 13, 2004, ATC personnel
<br /> collected groundwater samples from monitoring wells MW 1 through MW5, MW6a, MW6b,
<br /> MW6c, MW7a, MW7b, MW7c, MWS, MW9a, MW9b, MW9c, MW10a, MW10b, MW10c and
<br /> ' EWL The locations of the wells are shown on Figure 2.
<br /> The depth to water was measured in all wells prior to collection of groundwater samples. The
<br /> ' pH, electrical conductivity, and temperature were then measured in the groundwater purged from
<br /> the monitoring wells and recorded. Turbidity was visually observed and recorded. A minimum of
<br /> three well casing volumes were purged from each monitoring well prior to sampling, except for
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<br /> wells MW6c, MW7c, MW9b, MW10a, and MW10c on September 13, 2004 which were bailed
<br /> dry. The wells were allowed to recover and samples were collected from each well using
<br /> disposable polyethylene bailers. After samples were collected, dissolved oxygen (DO)
<br /> concentrations were measured.
<br /> s:1268231QM repons12004 3QR.doc 2 ATC Associates Inc.
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