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1 Mr Jeff Wong 10 Page 2 of 5 ' During the reporting period a Ground Zero technician measured free product thickness and removed approximately 18 4 gallons of product/water mixture from well MW 1 The passive skimmer was installed in the well on May 19, 2003, and removed in late October 2003 in anticipation of starting up ' the treatment system The skimmer was temporarily returned to well MW 1 during a period of system downtime between November 21 and December 3, 2003 ' Table 1 summarizes the measured product thickness and volume removed from well MW I since August 16, 2001 Attachment A contains copies of field logs related to product monitoring and removal during ' the reporting period 3.0 INTERIM GROUNDWATER EXTRACTION AND TREATMENT SYSTEM On October 29 2003, gr samples les were collected from well MWI to satisfy California Regional p Water Quality Control Board, Central Valley Region (RWQCB) Wastewater Discharge Requirements (WDRs) General Order No R5-2003-004412, which was issued by the RWQCB in a letter dated November 5, 2003 After pressure testing the system and setting the fluid level switches in the well, the system was put into operation on November 5, 2003 The initial flow rate through the system was measured at approximately • 19 gallons per minute A sampling program of the treatment system influent, effluent, and intermediate ' carbon units was established pursuant to the WDRs The treatment system was shut down on November 18, 2003 due to a premature breakthrough of carbon, ' MTBE was detected in the effluent sample at 9 2 parts per billion (ppb) Based upon an analysis of breakthrough presented in correspondence to the RWQCB dated January 5, 2004, we feel that the primary factors that contributed to the accelerated breakthrough of the carbon mcludedy excessive ' drawdown in the extraction well and btofouling/scaling in the carbon units The system was restarted on December 11, 2003 after the carbon was replaced in the primary and secondary 2,000-pound carbon units and a 200-pound "polish' carbon unit was added to the system In addition, Ground Zero is ' currently installing a compact, low-profile air stripper prior to and in series with the liquid phase carbon units,which will allow a substantial increase in flow capacity of the treatment system ' With the exception of the period of inoperation between November 18 and December 11, 2003, the system generally operated continuously Approximately 62,250 gallons of water had been treated through December 30, 2003, at an average flow rate of approximately 14 gallons per minute (gpm) during ' operation Analytical results of samples collected from the treatment system through December 31, 2003 are summarized in Table 2 Treatment system flow data and maintenance notes through December 31, 2003 are summarized in Table 3 Treatment system monitoring logs and laboratory-reports are included in ' Attachments B and C, respectively ' 4 0 INSTALLATION,DEVELOPMENT AND SAMPLING OF ADDITIONAL WELLS • Between October 6 and October 23, 2003 Ground Zero conducted additional subsurface investigation to ' further investigate the lateral extent of contamination in the shallow aquifer north of former tank pit, and determine if the former water supply well acted as a conduit to deeper zone groundwater ' GIGROUNDZEITULEBURG\Reporm\QMR1200314QM2003 doc