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PILKINGTON NORTH AMERICA,INC.
<br /> SITE BACKGROUND
<br /> On June 10 and 11, 1999, six diesel recovery wells (RW-1 through RW-6) were installed in accordance
<br /> with the Work Plan - Standby Generator Diesel Supply Line/Installation of Product Recovery Wells,
<br /> dated March 23, 1999. Three monitor wells were installed concurrently with the recovery well (RW)
<br /> installations as originally proposed by the Work Plan - Standby Generator Diesel Supply Line/Product
<br /> Recovery System Installation and Monitoring Well Installation, dated June 23, 1997. The well
<br /> installations were conducted with the approval of Mr. Philip Isorena of the CRWQCB.
<br /> A diesel skimmer was installed at RW-2 on June 18, 1999. Between June 18 and September 29, 1999,
<br /> approximately 3.1 gallons of diesel were removed from RW-2. Diesel recovery at RW-2 waned to
<br /> virtually nothing during the final weeks of this period and therefore, diesel recovery operations at RW-2
<br /> were discontinued.
<br /> Condor conducted quarterly groundwater monitoring at the site on September 14, 1999. In the report
<br /> describing the monitoring results and diesel recovery efforts dated October 13, 1999, Condor
<br /> recommended several proposed actions based on the results of the groundwater monitoring and diesel
<br /> skimming. The proposed actions included discontinuation of diesel skimming, continued quarterly
<br /> monitoring of monitor wells MW-1, MW-2 and MW-3, quarterly monitoring of two facility basement
<br /> sumps, and quarterly monitoring of natural attenuation parameters at MW-3 and RW-1. In a letter dated
<br /> May 11, 2000, Mr. Isorena of the CRWQCB provided several comments regarding the report and
<br /> recommendations and requested a response to his comments. Mr. Isorena concurred with the proposal to
<br /> sample the basement sumps but also indicated that the proposed actions were insufficient to address
<br /> down-gradient and natural attenuation monitoring at the site. In the letter dated May 31, 2000 Condor
<br /> responded to Mr. Isorena's comments by indicating that MW-2 would also be monitored for natural
<br /> attenuation parameters and that down-gradient monitoring, in the form of diesel product measurements at
<br /> RW-2 and sample collection at the facility basement sumps, would continue. In addition, Condor
<br /> proposed that monthly, intermittent diesel skimming at RW-2 be initiated based on recent diesel thickness
<br /> measurements indicating that approximately two feet of diesel product had accumulated in the well since
<br /> diesel recovery operations were discontinued on September 29, 1999.
<br /> First, second, third, and fourth quarter, 2000 groundwater monitoring activities were conducted by
<br /> Condor at the site on January 28, May 24, August 22, and November 16, 2000, respectively. Condor
<br /> prepared reports for the monitoring events, dated May 24, June 29, September 30, and December 18,
<br /> 2000, respectively. Monthly diesel skimming operations at RW-2 were initiated in July 2000. Results of
<br /> the monthly skimming are included in the quarterly groundwater monitoring reports. Monitoring of the
<br /> facility basement sumps was initiated during the May 2000 monitoring event. Testing of natural
<br /> attenuation parameters was initiated during the August 2000 monitoring event.
<br /> Analyses of water samples collected at the site for polynuclear aromatic compounds (PNAs) was
<br /> discontinued beginning with the August 2001 monitoring event, based on historical results and with the
<br /> concurrence of Mr. Isorena of the CRWQCB.
<br /> The first, second, third, and fourth quarter, 2001 quarterly groundwater monitoring activities were
<br /> conducted by Condor at the site on February 16, May 14, August 28, and November 14, 2001,
<br /> respectively. Condor prepared reports for the monitoring events dated March 20, June 30, October 4,
<br /> 2001 and January 7, 2002. Monthly diesel skimming operations continued at RW-2 with an annual
<br /> recovery of approximately 5.5 gallons of product and a cumulative product removal total of 15 gallons.
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