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URS Mr. Robert McClellon January 31,2011 Page 2 monitoring wells were installed at the site on June 12,2006. Following the installation of the groundwater 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. During the third quarter groundwater monitoring activities,damage was observed at the top of groundwater monitoring well MW-1. FIELD ACTIVITIES On November 23,2010,the damage to groundwater monitoring well MW-1 was repaired. The damaged portion at the top of monitoring well MW-1 was removed and an extension was added to the top of the monitoring well. A new Christy box was installed over the top of the repaired monitoring well. To prevent this type of damage from reoccurring,three bollards were installed around this monitoring well. In addition,the vertical elevation of the three groundwater monitoring wells were resurveyed. Landfill gas concentrations were measured within the gas migration monitoring probes, extraction wells,and passive vents, and quarterly groundwater monitoring activities were completed on December 16, 2010. Using a handheld portable landfill gas monitor, a GEM 2000,each gas-migration monitoring probe, each extraction well, and each passive vent was measured for methane, oxygen,and carbon dioxide. These measurements were recorded in a field logbook. Groundwater samples were collected from the three monitoring wells using the following procedures: • The water level within each monitoring well was measured using an electronic water level sounder. • Prior to groundwater sample collection, each well was purged using a bailer. During purging, groundwater parameters (pH,temperature, and conductivity)were recorded on the Monitoring Well Sampling Data form(Attachment 1) at least once per well casing volume. Purging was completed when the groundwater parameters had stabilized to within 10% or the monitoring well was bailed dry. The purged water was placed in a 55-gallon drum,pending disposal. • A groundwater sample, collected from each well using a bailer,was placed into the analytical laboratory-prepared sample containers. • Groundwater samples were labeled and placed in an ice chest with ice. The ice chest was shipped to EMAX Laboratories, Inc. in Torrance,California,under proper chain-of-custody procedures for selected dissolved metals analyses by United States Environmental Protection Agency(EPA) Methods 6010/6020/7470 and TDS analysis by EPA Method 160.1. H:\Wprocess\25532\WorldEnterprise\Quarterly Rpt\2010\4Q10\01201 Ldoc