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' diameter for Well MW-6 was four inches, a larger diameter jet bit was utilized (see photograph #17, Figure 5). After re-positioning the pump truck ' (RCM®) near MW-6, the BSK project manager collected a second water sample at 11:30. The sample was labeled Sample #3 Pump Water and placed in an ice chest with ice. ' The BSK project manager kept count of drill stem sections. The jet bit was initially positioned at 124 feet inside the casing of MW-6. Cement grout was pumped under pressure until groundwater flowed from the riser casing. Based on a current water level measurement and casing depth, it was estimated that approximately a 60-foot grout column existed inside the well casing. The drill ' stem was pulled so that a perforation could be completed at 110 feet. At the 110-foot interval the only return flow was clear groundwater. This was also the case for the perforation interval at 103 feet. During the perforation operation at the 97-foot interval, cement grout return flow was observed. The BSK project manager left the site at 13:30 to deliver the two water ' samples to Chromalab. The two water samples were transferred to a Chromalab representative under a Chain-of-Custody Record. ' The BSK field supervisor called the BSK project manager at 15:20 and informed him that the jet grouting of MW-6 was completed and that he had ' the signed-off well destruction permit for six wells from the SJPHS inspector. Three containment pools were used to store overflow grout. ' 3.4 June 11 Activities - The BSK field supervisor met with Straub Construction Company (subcontractor hired by Remediation Services, Inc.) at 08:00. A three-foot square area immediately adjacent to MW-2 was excavated with a backhoe to remove the eight-inch riser casing, well vault box, annulus seal and grouted two-inch well casing to three feet. A portion of the solidified grout from inside the two-inch PVC casing was placed into two separate clean jars. Photograph #21, Figure 5 shows the grout penetrating into the structural concrete annulus seal at approximately three feet below existing site grade. The subcontractor (Straub) moved his crew and equipment to well locations MW-4 and 6 where they started to break up the solidified grout in the containment pools. From this location, the subcontractor moved to MW-3, then to MW-5, and then on to MW-1. This operation is illustrated in photographs #18, #19, and #20, Figure 5. ' The broken pieces of solidified grout from containment pools and rinsate boxes was loaded into a dump truck and hauled to a recycler of construction debris. Cal West arrived on site at approximately 11:00 to perform saw cuts in the asphalt pavement at Wells MW-1, 3, 4, 5, and 6. The typical area of the saw ' cut is illustrated in photograph #22, Figure 5 along with the procedure used 8 1 • &Associates