ARCHIVED REPORTS_XR0011317 - Laserfiche WebLink

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On August 15, 2000, Mark Jerpbak, geologist with JJW, Inc., arrived on site at 0730 - he met with a representative of Valley Wholesale Drug Co., and checked the site for access. A V & W Drilling CME -75 auger rig, support truck and decontamination trailer arrived at 0750; Robert Vickery driller. Equipment consisted of sufficient clean, 8" hollow stem augers to complete each well. Two California Modified Split- Spoon core samplers allowed one to be in use while the other was being decontam- inated. The rig was positioned on the site selected for MW-4, shown on PLATE I. Operations began at 0810; the first 4 feet was hand augered to prevent possible damage to unidentified lines or pipes. None were encountered. Clean augers were then used to advance the soil boring. At a depth of 5' below grade, the core barrel, equipped with clean, 2"diameter metal sleeves was lowered into the augers and driven from 5' to 6' 6". The barrel was retrieved, placed upon a clean surface, and carefully opened. Mr. Jerpbak quickly sealed one of the tubes with teflon tape & duct tape, clearly labeled it and placed it on ice pending transfer to a laboratory for analysis. A portion of one of the remaining tubes was placed in a zip lock bag and set aside for screening. After describing the lithology and noting any odors, the remaining core material was placed in metal drums for later disposal. The portion of core in the plastic bag was checked for contaminants by inserting the probe of a field calibrated PID meter into the bag and recording the reading. William Hunter, RG, arrived on location at 0840 to witness field operations. Jeffrey Wong, REHS, from the San Joaquin County EHS, arrived at 0955. Soil samples were taken at 10', 15', 20', & 25' as described above. A complete description of the blow counts, lithology, odor, and PID readings are given on PLATE II. After obtaining the final core, 2", blank & slotted flush screw-threaded PVC was run in the hole. It was fitted with a blank screw cap on bottom, 20' of machine-cut slots, and 5' of blank. The annular space between the augers and casing was filled with #3 graded gravel poured from the surface. The augers were pulled out as the sand was placed. The top of the sand fill was at 4' below ground surface, one foot above the top of the screen. A bentonite seal was placed from 4' bgs to 3' bgl, and the top of the casing was covered to prevent entry of foreign materials; refer to PLATE V for well construction details. The rig was then moved and set up over the location for MW-5 at 0955 as shown on PLATE I. The first 4' was hand-angered, and then hollow-stem augers were run and advanced to 5' bgl where the first core was taken. It was preserved using the same protocol as described above. Additional cores were taken at 10`, and 15'. There was no recovery from the core taken at 20'. Cores were taken at 25' and 30'. Details of blow counts, lithology, odors, & PID readings are given on PLATE Iii. Although no odors or visible evidence of petroleum substances were noted, high PID Wm. I Hunter&Associates 3