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URS Mr.Robert McClellon October 31,2012 Page 2 monitoring wells were installed at the site on June 12, 2006. Following the installation of the ground- water monitoring wells, groundwater samples were collected quarterly and analyzed for VOCs. Mr. Ross Atkinson of the Regional Water Quality Control Board(RWQCB), Central Valley Region, requested that groundwater samples be collected and analyzed for metals and general minerals(only total dissolved solids [TDS] after the first event)starting in 4Q06. In a meeting on May 24,2007,Mr. Atkinson concurred with the recommendation in the Quarterly Monitoring Report dated April 30, 2007, to suspend the groundwater monitoring activities for VOCs. In the IQ I letter report to SJCEHD dated April 29, 2011, URS recommended reducing the frequency of the monitoring activities from quarterly to annually. SJCEHD agreed with URS' recommendation. The annual monitoring activities are usually conducted during the fourth quarter of each year, At the request of Ms. Subbotnikova of SJCEHD,the annual monitoring activities for this year were conducted during the third quarter. In a letter to RWQCB dated May 20,2011,URS recommended no further action for groundwater activities. RWQCB agreed that on-site groundwater issues had been resolved to their satisfaction and issued a letter to proceed with well decommissioning on December 2, 2011. URS decommissioned the groundwater monitoring wells on December 9,2012. FIELD ACTIVITIES Annual Monitoring Activities On September 12,2012, URS measured landfill gas concentrations(i.e. methane, oxygen, and carbon dioxide)using a handheld portable gas monitor, a GEW 2000, within the gas migration monitoring probes(VW-1 though VW-10), extraction wells(EW-1 and EW-2), and passive vents(VP-1 through VP-4). URS recorded these measurements in the project logbook RESULTS The methane concentrations measured during the quarter were 0% in all gas-migration monitoring probes,except for a result of 0.6% in VW-6S. Methane concentrations measured in the vapor extraction wells were 7.1% in EW-1 and 3.4%in EW-2. Methane concentrations measured in the passive vents were 3.8% in VP-1, 4.3% in VP-2, 5.3% in VP-3, and 4.6% in VP-4. Oxygen concentrations measured at all sample locations during the quarter ranged from 0.0%to 20.5%. Carbon dioxide concentrations measured at all sample locations during the quarter ranged from 0.6%to 29.0%. Table 1 summarizes results for each probe each extraction well and each passive vent. H:\Wprocess\25532\WorldEnterpriseNQuarterly RPt\2012\Text doc