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' to remove the pavement section and start the excavation. The condition of the removed annulus and grout-filled casing from MW-3 is shown in ' photograph #23, Figure 5. A grout "pancake" formed at the base of the excavation for MW-5 is shown in photograph #24, Figure 5. A portion of the grout-filled casing recovered from MW-5 is shown in photograph #25, Figure ' 6. Two samples of the solidified grout from within each well casing were collected in clean jars, labeled, and placed in an ice chest with ice. ' The excavations for MW-1, 3, 4, 5, and 6 were backfilled with a 5-sack portland cement concrete mix to within approximately four inches of final pavement grade (see photograph # 26, Figure 6). The surface at these well locations was paved with an asphalt cold-patch mix compacted with a "turtle' vibraplate (see photograph #27, Figure 6). At 16:00, the BSK representative collected a water sample from the two-inch water supply line on the west side ' of Building #5. BSK and the subcontractor demobilized at approximately 18:00. ' 3.5 June 15 - Activities - Portions of the annulus seal, PVC well casing, and solidified grout from the six abandoned groundwater monitoring wells, which were transported back to the BSK office (Pleasanton),were visually examined ' by the BSK project manager and photographed for project records. Photograph #28, Figure 6 shows the cut made on the well casing from MW-1 ' at three feet. Photograph #29, Figure 6 shows the cut made on MW-2 (note that annulus seal from MW-2 consisted of structural concrete rather than neat cement). Photograph #31, Figure 6 illustrates penetration of the grout into ' the annulus seal (structural concrete) of MW-3. Also, note on Photograph #31 that the grout had penetrated through the annulus seal and formed a "grout cake" on the outside of the seal (illustrated by "ears" shown on the left ' side of the seal). Photograph #32, Figure 6 shows the cut at three feet on MW-4. Photograph #33, Figure 7 shows the cut performed on MW-5 at three feet and portions of grout which penetrated beyond the annulus seal. ' Photograph #34, Figure 7 shows that the jet tool fractured the PVC casing at three feet on MW-6 but was unable to cut the casing at this interval owing to the fact that one of the carbide inserts blew-out at this interval. Additional ' discussion on this latter item is presented in Section 5.0. ' 4.0 ANALYSIS OF MIXING WATER 4.1 Sample Collection - As previously discussed, samples of the mixing water were ' collected from the bottom discharge on the pump truck (refer to Sections 3.2 and 3.3). On June 11, a water sample was collected in a clean one liter amber glass jar from the two-inch supply line located on the west side of ' Building 5. Upon collection, the sample was sealed, labeled and placed in an ice chest with ice. The sample was transported back to the Bay Area by a BSK representative and then transferred under Chain-of-Custody ' documentation on June 12 to Chromalab, Inc. (refer to Appendix Q. 9 • &Associates