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i 23 January 2015 AGE Project No . 06- 1457 � L Page 5 of 6 -i Appropriately sealed and labeled samples will be placed in a chilled container under ice ✓� d� and transported under chain-of-custody procedure to a CDPH -certified laboratory. Each sample container will be labeled with sample designation , time , date and sampler's nJ � � initials . >ti , 9 Abandonment � 3 . 1 . 3 . Borin Abandonm � Following completion of each of the three proposed borings , each location 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 will be notified for grout inspection at least 48 hours prior to conducting grouting procedures . 3 . 2 . MONITORING WELL INSTALLATION _ A total of three intermediate screened groundwater monitoring wells are proposed for installation in areas illustrated in Figure 3 . All three monitoring wells are proposed for installation from 75 to 80 feet bsg (similar to previously installed wells MW-5 , MW7 and MW- 10 [Table 21 or based on field observations during advancement of the pilot borings . A deterrfiVation on the installation of the wells will be completed following soil sample collection . 2 3 . 3 . WELL COMPLETION Following advancement of pilot borings , 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, 75-foot Schedule 40 PVC blank casing and a 5-foot section 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 of the filter pack , the well will be surged to assist filter pack settling . Additional sand will be added if settling occurs . A nominal 3-foot bentonite seal (TR-30 coated pellets) will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the well . The bentonite seal will be formed by pouring bentonite pellets into the annular space between the hollow-stem augers and well casing and allowing them to settle on the filter pack. Bentonite pellets will be hydrated a minimum of 30 minutes or as specified by the manufacturer prior to grouting using five gallons of water. Advances! CeoEnvironmenfal Inc.