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09 October 2013 AGE-NC Project No. 11 -1847 Page 4 of 5 3 . 1 , BORING ADVANCEMENT AND SOIL SAMPLING Utilizing a truck-mounted , hollow-stem drill rig equipped with 8 .25-inch diameter hollow- stem augers, three pilot soil borings will be advanced to a depth of approximately 45 feet bsg . Beginning at 5 feet bsg , relatively undisturbed soil samples will be collected from all soil boring locations at 5-foot intervals using a California modified split-spoon sampler fitted with 2-inch diameter, 6-inch long steel sleeves . Upon removal from the sampler, the sample sleeves will be separated with a knife . The exposed ends of the second sleeve will be covered with Teflon sheets , capped , and sealed with tape. Soils sampled in the borings will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System (USCS ). Additionally, soil samples will be field screened for the presence of volatile organic compounds using an organic vapor meter (OVM ), equipped with a photo-ionization detector (PID). Soil sample descriptions and OVM readings will be recorded on a log for each boring . Following sample collection , each preserved sample sleeve will be labeled with the boring location , depth , time , date , and sampler's initials . Appropriately sealed and labeled samples will be placed in a chilled container and transported under chain of custody to a CDPH-certified laboratory for analysis for the constituents listed in Section 2 .2 . i 3 .2 . WELL COMPLETION AND ELEVATION SURVEY The pilot soil borings will be completed as groundwater monitoring wells utilizing a 2-inch diameter, Schedule 40 PVC blank well casing and 0 .020-inch slotted well screen installed from 25 feet to 45 feet bsg . A diagram of the proposed monitoring well construction is depicted on Figure 3 . After installing the well casing in each pilot boring , a filter pack material consisting of pre- washed #3 Lonestar sand will be added through the augers from total depth to approximately 2 feet above the screened interval . Following placement of the filter pack, the well will be surged to assist in settling the filter pack. Additional sand will be added if settling occurs . A one-foot bentonite seal will be placed above the filter pack to minimize the potential for grout penetration into the screened section of the wells . The bentonite seal will be formed by pouring bentonite chips into the annulus and allowing them to settle on the filter pack. The bentonite chips will be allowed to hydrate for the du ation of time specified by the manufacture, prior to grouting . The remaining annular sp ce will be filled to within one foot of the ground surface with a cement grout. The grout mixture will consist of Type 1/II v� X11Irl / ' Advanced GeoEnvironmentaI, Inc.