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1 � <br /> ' into the screen section of the sampler. The ground water samples were poured from the bailer into <br /> laboratory-supplied 40-m1 VOA vials containing 0.5-m1 of 18-percent hydrochloric acid as sample <br /> ' preservative for BTEX, TPH-g, and fuel oxygenating compound analysis. Samples analyzed for <br /> TPH-d were placed into one-liter amber glass containers. <br /> ' Following sample collection,the preserved sample containers were labeled with the boring location, <br /> depth,time, date and sampler's initials. Appropriately sealed and labeled samples were placed in a <br /> chilled container under ice and transported under chain-of-custody procedure to Alpha Analytical <br /> ' Laboratories, Inc. and Kiff Analytical, DHS-certified laboratories. <br /> ' A.3. MONITORING WELL INSTALLATION <br /> Following completion of drilling and sampling soil borings B-4 and B-5, the soil borings were <br /> ' completed as ground water monitoring well MW-4 and MW-5,respectively. The monitoring wells <br /> were constructed with 2-inch diameter Schedule 40 PVC 0.010-inch slotted well screen and casing. <br /> Monitoring well MW-4 was completed to a total depth of 21 feet bsg and installed with 15 feet of <br /> ' well screen section extending from 6 to 21 feet bsg. Monitoring well MW-5 was completed to a total <br /> depth of 17 feet bsg and installed with 10 feet of well screen section extending from 6.5 to 16.5 feet <br /> ' bsg. The well screen sections were installed across the observed water table level. During drilling <br /> activities, ground water was encountered at approximately eight feet bsg. <br /> After installation of the well casing, filter pack material consisting of pre-washed #2112 Lonestar <br /> sand was added from the bottom of the borehole to approximately one foot above the screened <br /> interval. Following placement of the filter pack, the well was surged to settle the filter pack sand. <br /> Additional sand was added to a level one foot above the screen section. <br /> A nominal two-foot bentonite seal was placed above the filter pack to minimize the potential of grout <br /> ' penetration into the screened section of the well. The bentonite seal was formed by pouring bentonite <br /> chips into the annulus and allowing them to settle on the filter pack. Bentonite chips were hydrated <br /> using five gallons of water. The bentonite chips were allowed to hydrate for a minimum of one-half <br /> ' hour prior to grouting. <br /> The remaining annular space was filled to within one foot of the ground surface with a cement grout. <br /> ' The grout mixture consisted of Type I/II portland neat cement and not more than 6 gallons of water <br /> per 94-pound sack of cement. Grouting procedures were approved by PHS-EHD personnel. <br /> ' The top of the well casings were secured with a water-proof, locking caps. The wells were protected <br /> with a traffic-rated, water-tight circular vault installed approximately one-inch above surface grade. <br /> 1 <br /> A.4. WELL DEVELOPMENT <br /> ' Well development procedures consisted of a combination of bailing to remove the major portion of <br /> ifine-grained sediment from inside the wells, surging to flush out or draw in sediment from the filter <br /> ' Advanced GeoEnvironmental Inc. <br /> 1 <br />