ARCHIVED REPORTS_XR0010333 - Laserfiche WebLink

Home Browse Search

Another portion of the core was placed in a sealed plastic bag & screened with the PTD meter using the same technique described earlier. Additional details are included on EXHIBIT XIV. Drill cuttings & unused core material were placed in steel drums_ No odors or evidence of contamination, were noted, and the PID meter gave a zero reading from the bagged material Two core barrels were available; while one was being used to take a core, the other was thoroughly decontaminated with Alconox & clean water, filled with clean metal tubes, and laid aside until needed. Michael Collins, REHS, from the San Joaquin County PHS, EHD, arrived at 1015 to witness operations. The augers were advanced to 50' , at which point the properly prepared core barrel was lowered into the hole, and a core was taken from 50' to 51 ' 6" . The same field procedures described above were followed; there was no reading from the PID when placed in a sealed plastic bag containing some of the cored sediment. Details are given on EXHIBIT XIV. Another core was taken from 60' - 61 ' 6" and handled by the same . procedures. No odor or evidence of contamination was noted, and no PID reading were recorded. Refer to the above exhibit for details. The San Joaquin County representative left. The lithology consisted of tan to brown dense clay; slightly plastic & firm. Drilling became quite difficult, and at 1145 the clutch on the drive shaft burned out. Operations were suspended until 1400 while the clutch was replaced. Drilling continued to 70' and a core was taken from 70' - 71' 6" . When the core was retrieved, the bottom was wet, indicating that groundwater had been encountered. Recovery consisted of 12" of wet, tan silty clay; very dense, sli.ghly friable. A sample tested with the PID showed zero. A tape was lowered in the flights & located water at 71-72' , which agreed with depths measured in monitoring wells on the property. A core sample was preserved according to the field procedures described earlier. The auger flights were advanced to 83' preparatory to completion as a monitoring well. The blanking plug was retrieved; it had some very wet silty clay on the bottom. 4" OD, blank & slotted flush screw .joint PVC was made up and run inside the augers to 83' _ The bottom 15' had . 02" shop-made slots & was equipped with a screw-type bottom cap. The crest was blank, screw-thread casing; no cement was used in making up the casing string. The annular space from bottom to 65' was filled with 7 sacks of 03 lonestar screened sand, which was poured down the annulus from the surface after sealing the top of the PVC with a plastic cap The pipe was vibrated frequently during placement of the gravel 6