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B: \WPLATEXT.DOC casing and will be done to . 01 feet with reference to mean sea • level as the benchmark. SAMPLE METHODS. WEGE will supervise the drilling of two ground water monitoring wells to the 70 foot depth. Drilling activities , cuttings and samples will be screened with a Photo ionizing detector (PID) HNu with a 10 . 2 ev bulb. Samples will be obtained every 5 feet and at noticable formation changes . Samples will be used for lithology and selected samples will be preserved and chain of custody E delivered to a DHS certified laboratory for analysis . These borings will be advanced to the 70 foot depth. Any samples that field screen positive will be sealed, preserved, and chain of custody delivered to MATRIX Laboratories (DHS-359 ) , formerly Chemtech Analytical Laboratories , for analysis of Total Petroleum Hydrocarbons-gasoline range and BTEX. If field screening indicates the absence of contamination, the 45 , 50 and 55/or top of ground water and the 70 (termination of boring) foot samples will be sealed, preserved, and chain of custody delivered to MATRIX Laboratories (DHS-359 ) , formerly Chemtech Analytical Laboratories , for analysis of Total Petroleum Hydrocarbons and BTEX (depths where samples were positive in boring 1 , boring 2 , boring 3 , MW-1 , MW-2, MW-3 , and MW-10) . PROCEDURE FOR DRILLING SOIL BORINGS OR MONITOR WELLS • A truck-mounted drilling rig with ten inch hollow stem augers will be used to drill the monitoring well . The rig equipment and augers will be steam cleaned prior to use, and the sampling equipment will be cleaned in the same fashion between each sampling interval . In addition, all lubricated parts that are to enter or approach the borings are lubricated with olive oil . To document the soil samples taken at each interval during the drilling of the monitoring well , a WEGE field geologist prepares a boring log. The samples are described and categorized using lithologic descriptions and the Unified Soils Classification System (Appendix B, Monitor Well Boring and Construction Logs ) . Relatively undisturbed soil samples will be collected at five-foot intervals , at changes of lithology, and at the soil water interface using a California Split Spoon Sampler equipped with four 21IX6" clean brass sleeves . Borings are advanced to the desired depth with the hollow stem auger, and the center rod center plug pilot bit assembly is withdrawn. The sampler is then lowered through the auger to the bottom of the borehole and driven 28" into the soil with a 140-pound hammer. Prior to preservation, soil samples from each interval are field-checked for the presence of odor , vapor , and visible staining. In addition, a vapor analysis is performed on each sample using a hand-held photo ionizing detector (PID ) which is calibrated daily with a 50 ppm • gasoline vapor standard. At each sample interval , the brass 4