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' h'q KLEINFELDER advanced in the Mission Site Area and two in the Pershing Site area One CPT from each area was advanced to a depth of approximately 40 feet bgs The CPTs were advanced to obtain information ' regarding the lzthology in these two areas for trench stability issues These CPT locations are labeled PT-13 through PT-18 (Plates 1 and 2) The CPT work and findings will be summarized in a separate geotechmeal report, since soil and groundwater samples were not collected from the CPT borings Nine (9) pushprobes (GP-8 through GP-16) were advanced in the Mission Site Area on April 15, 2003, over approximately 640 linear feet at intervals ranging from approximately 55 to 115 feet Six (6) pushprobes (GP-17 through GP-22) were advanced in the Pershing Site Area on April 18, 2003, over approximately 400 linear feet at intervals ranging from approximately 50 to 115 feet ' The pushprobes were continuously advanced in five foot intervals using a pneumatically dnven steel probe to maximum depths ranging from 20 to 25 feet bgs During advancement of the probes the soil samples were logged for lithologic classification based on the Unified Soil Classification System (USCS) The sample probe was lowered to the desired sampling depth and driven into the soil A total of fifteen (15) soil samples were collected between the two areas, one from each of the pushprobe locations at depth intervals of approximately 9% to 10 feet bgs Soil samples were obtained by inserting acetate liners into the probe and by cutting out the desired sample interval from the acetate liners, and sealing the ends with Teflon tape and plastic caps The logs of the pushprobes are located in Appendix A After completion of each boring a grab groundwater sample was collected in each of the 15 push probes Groundwater was encountered at depths ranging from 9% to 13 feet bgs in the Mission area and at depths ranging from 13% to 15 feet bgs in the Pershing Area Groundwater appeared to stabilize at depths ranging from 10 to 12 feet bgs, if boring material was permeable enough to ' allow groundwater to rise within the boring prior to sealing the boring Groundwater recovery was noticeably slower in the Pershing area due to tighter soils (e g clays and silts) The groundwater samples were collected either by a single use disposable polypropylene bailer or by ' use of a disposable polypropylene tubing, stainless steel ball valve and PVC piping If the boring was suspected of encountering caving or heaving sands, a 1-inch PVC pipe with a 5 to 10 foot screened interval was lowered into the boring The tubing and check valve was lowered into the piping and groundwater was collected by positive displacement The groundwater samples were decanted directly from the bailers or tubing into pre-cleaned laboratory provided bottles for the requested analyses After collection, the soil and groundwater samples were labeled, logged on a chain-of-custody form, and immediately stored in an iced cooler The samples were transported under chain-of- custody control to Kletrifelder's office and then transported by courier in a sealed container to Alpha Analytical of Sparks, Nevada for the requested chemical analysis Alpha is certified by the California Department of Health Services (DHS) to perform the requested analyses The laboratory data sheets and chain-of-custody records are included in Appendix D • 28699 E01 /ST03R793 Page 4 of 16 Copyright 2003,Kleinfelder,Inc July 21,2003