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<br /> Pilkington North America,Inc.
<br /> Site Background
<br /> ' Page 3 of 13
<br /> First, second, and third quarter 2004 quarterly groundwater monitoring activities were conducted by
<br /> ' Condor at the site on February 9, May 13-14, and August 5-6, 2004, respectively. Condor prepared
<br /> reports for the monitoring events dated March 23, July 16, and October 8, 2004. The east/southeast
<br /> groundwater gradient estimated during the first, second, and third quarter 2004 groundwater monitoring
<br /> events was consistent with the range of historical groundwater gradients estimated for the site since
<br /> monitoring events was initiated on June 21, 1999. Diesel was detected in MW-2 and the SW Sump during
<br /> the February 2004 monitoring event, consistent with recent laboratory analytical results. Diesel was not
<br /> detected in any of the samples collected in May 2004. Laboratory analysis of the third quarter 2004
<br /> ' samples indicated that diesel was detected in the samples from MW-2,MW-3, SE-sump, and SW-sump.
<br /> Monthly diesel skimming operations continued at RW-3 and RW4. Skimming operations were expanded
<br /> ' to include RW-2 and RW-6 when water and product levels were appropriate. Combinations of the active
<br /> skimmer, two passive skimmers, absorbent socks, and bailing were used in diesel recovery operations.
<br /> Results of the monthly skimming were included in the 2004 quarterly groundwater monitoring reports. At
<br /> ' the end of the third quarter 2004, a cumulative product removal of 127.7 gallons was estimated for the
<br /> site.
<br /> During the fourth quarterly monitoring event conducted at the Site on November 24, 2004, Condor
<br /> sampled two sumps (SE sump and SW sump) and three monitoring wells (MW-1, MW-2, and MW-3).
<br /> Since the previous quarterly monitoring event, the average groundwater elevation measured in the three
<br /> Site monitoring wells has decreased by 0.39 feet. The calculated groundwater gradient was 0.0025 feet
<br /> ' per foot (ft/ft) to the southeast on November 24, 2004. TPH-D, TPH-K, and TPH-MO were not detected
<br /> at or above the laboratory reported detection limits in monitor well MW-1 and MW-3. TPH-D was
<br /> detected in monitoring wells MW-2 and in the SE and SW sumps.
<br /> ' Five diesel recovery events were conducted at the Site from September 3, 2004 through December 23,
<br /> 2004. Free product was observed in five recovery wells (RW-1, RW-2, RW-3, RW4, and RW-6). A total
<br /> of 4.92 gallons of product was recovered during this period. Product recovery from the Site's recovery
<br /> wells has produced a cumulative total of approximately 132.62 gallons of recovered diesel.
<br /> Ten diesel recovery events were conducted at the Site from January 11, 2005 through April 15,2005. Free
<br /> product was observed in four recovery wells (RW-2, RW-3, RW-4, and RW-6). A total of 9.05 gallons of
<br /> product was recovered during the first quarter 2005. A cumulative total of approximately 141.67 gallons
<br /> of diesel was recovered from the Site's recovery wells since skimming operations commenced in June
<br /> t 1999.
<br /> During the first quarterly monitoring event conducted at the Site on February 8 and March 1, 2005,
<br /> Condor sampled two sumps (SE sump and SW sump) and three monitoring wells (MW-1, MW-2, and
<br /> MW-3). Groundwater elevation measurements collected on February 8, 2005 indicated an average depth
<br /> to groundwater of 13.16 feet below well collar survey points. The average groundwater elevation on
<br /> February 8, 2005 increased 1.60 feet since the previous monitoring event on November 24, 2004. The
<br /> calculated groundwater gradient on February 8, 2005 was 0.0019 ft/ft to the southeast. TPH-D, TPH-K,
<br /> and TPH-MO were not detected at or above the laboratory reported detection limits in monitoring wells
<br /> ' MW-1 and MW-3. TPH-D were detected in monitor well MW-2 and in the SE and SW sumps.
<br /> On May 9, 2005, Condor surveyed the three Site monitoring wells and the six recovery wells. The wells
<br /> t had previously been surveyed to an arbitrary datum and were consequently re-surveyed in accordance
<br /> with the SWRCB's Survey XYZ Guidelines and Restrictions —Electronic Deliverable Format and Data
<br /> Dictionary manual revised in April 2005. The survey was conducted to comply with AB 2886 (Water
<br /> Code Sections 13195 — 13198) under the supervision of a licensed land surveyor. The results of the
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