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• Provided greater than 48-hour notification to the SJCEHD prior to performing well destruction activities. • Provided the required 48-hour notification to the Underground Service Alert prior to job site mobilization (Ticket No. 243630). Field Activities The monitoring wells were destroyed between August 23 and 25, 2010, by pressure grouting the casing and annulus to the total depth of each well.The sealing material consisted of neat cement with a 5% mixture of bentonite. The cement was introduced with a tremie pipe extending to the bottom of each monitoring well. After the wells were grouted to a depth of approximately 3 feet below the ground surface, we utilized a backhoe to remove the upper 3 feet of casing and the concrete and soil from an area 12 inches larger than the original boreholes. Once the soil had been removed, additional grout was added to the casing and allowed to "mushroom" over the casing and into the surrounding 3- foot-deep excavation. The excavation was then backfilled with soil and concrete to the ground surface. Black dye was applied to the concrete at the ground surface in order to blend with the surrounding asphalt. The former location of well MW-12 was covered in soil and topped with sod to blend in with the surrounding lawn. The well casings were placed in a waste receptacle. The broken concrete was disposed of at F.T.G Construction Materials, Inc. in Lodi, California. Although our Workplan stated that per SJCEHD requirements and due to minor contamination remaining in vapor extraction wells VEW-1 and VEW-2, the destruction of these wells would require overdrilling the casing and annulus to the total depth of each well, Ms. Lori Duncan with the SJCEHD subsequently indicated that this was not required. Ms Duncan indicated that wells VEW-1 and VEW-2 could be destroyed as described above by pressure grouting and excavating the wells. Ms. Duncan further indicated that overdrilling of 1-inch-diameter air sparge wells ASW-1 through ASW-4 was not required, therefore these four wells were pressure grouted as described above. After the wells were grouted to approximately one foot below the ground surface, we removed the well boxes and added additional grout to fill the well casings to the top and over the casing. The well boxes were then removed using a jackhammer and placed in a waste receptacle. The top one foot of the annulus was backfilled with cement as necessary to match the surrounding ground surface. In addition to the well destruction activities, we also cut and capped the remediation lateral piping for wells VM-1, VM-2 and ASW-1 through ASW-4. LIMITATIONS This report has been prepared exclusively for Caltrans. The information contained herein is only valid as of the date of the report and should only be deemed conclusive with respect to the information obtained. No guarantee or warranty of the results of the report is implied within the intent of this report or any subsequent reports, correspondence or consultation either express or implied. We strived to perform the services summarized herein in accordance with the local standard of care in the geographic region at the time the services were rendered. Shop 10 Maintenance Station,Task Order No.94 Caltrans Contract No.06A1141,EA 43-910076 Project No.S9200-06-94 -2- September 9,2010