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i I 22 May 2013 AGE Project No . 11 - 1847 Page 5 of 6 3 . 1 .2 . Grab Groundwater Sampling Once the total depth ( 100 feet bsg ) is reached a Geoprobe (or similar) push -driven water sampling device will be advanced four feet below the total depth of the boring ( 104 feet bsg ) and then retracted to expose temporary well screen . Groundwater samples will be extracted from the borehole by dedicated disposable or polyethylene tubing through the hollow center of the push rods into the screen section . Samples will be analyzed for the constituents listed in Section 2 .3 . and will be collected into laboratory-supplied , non- preserved 40-ml Volatile Organic Analysis (VOA) vials . Appropriately sealed and labeled samples will be placed in a chilled container under ice and transported under chain-of-custody procedure to a CDPH-certified laboratory. Each sample containerwill be labeled with sample designation , time , date and sampler's initials. 3 . 1 . 3 . Boring Abandonment If it is determined that a monitoring well is not warranted for installation the soil borings will be permanently sealed to prevent vertical migration of potential contaminants . The soil boring will be abandoned by backfilling with cement grout from the total depth to surface grade utilizing tremie procedures . The top three to six inches of the boring abandonments will be completed flush to surface grade with native soils or concrete . The SJCEHD willbe notified for grout inspection at least 48 hours prior to conducting grouting procedures rl � 1fL ,x 3 .2 , MONITORING WELL INSTALLATION Contingent upon field observations during advancement of the pilot boring a deep screened groundwater monitoring well (screened 95 to 100 feet bsg ) may be installed within pilot boring B5 . A determination on the installation of the well will be completed following soil and groundwater sample collection . 3 .3 . WELL COMPLETION If warranted , and following advancement of the pilot boring , well casing , filter pack and sealing materials will be placed into the borehole through the interior of the hollow-stem augers . A 2-inch diameter, 95-foot Schedule 40 PVC blank casing and a 5-feet of 0 .020-inch slotted well screen will be installed in the borehole . After installing the well casing , filter pack material consisting of pre-washed #3 sand will be added from the bottom of the borehole to approximately two feet above the screened interval . Following placement Advanced GeaEnvirunmental, Inc.