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fro F -- APPENDIX A I j PROTOCOLS FOR WELL DRILLING,COMPLETION, DEVELOPMENT,AND SAMPLING i A.1 DRILLING The boreholes are drilled with a truck-mounted rotary drill using 10-inch outside diameter hollow-stem,continuous-flight augers. The borehole is drilled 10 feet below static water but will not penetrate competent clay layers that may act as effective aquitards. Drilling is terminated ! .6 after twoconsecutive sampling intervals intersect comparable, apparently impermeable clays ' below static water. Casing and sand are installed inside the inner opening as the augers are gradually removed. ? All augers, sampling rods, samplers, and downhole equipment are steam cleaned before drilling Y �! and between each new well. All drill 4uttings and fluids from steam cleaning are contained } it onsite in sealed 55-g0on drums. The drums are labeled with the borehole number,site descrip- tion tion (including owner's name),depth interval of soil contents,date,and monitoring equipment. readings. The drill cuttings are disposed of at proper facilities on the basis of soli sample analy- sis. 3 . A log of drilling and th "borei'oIe are-recorded by an EA-geologist overseeing the dri]ling.otsera tions and well installation. The boring logs are signed and dated and contain detailed geologic information,including des crpt ins of the soils classified according to the Unified Soil Classifi- ! C ation System, blow counts,OVA readings, moisture Conten " coater levels. . t.of the soils,and initial and static A.2 SOIL,SAMPLING Soil samples are collected at 5-foo t intervals and at any substantial changes of soil type, begin- ning at S feet below Bound surface, with a 2-inch-diameter, 1 S inch modified California split- 131 spoon sampler containing three 6-inch brass liners. The sampler and liners are steam cleaned. a before use in each hole; they are scrubbed in deionized water and Alconox detergent and. with deionized water after use at each sampling interval. Soil samples are collected to a total depth of the borehole unless heaving sand occurs. Every attempt is made to collect a-soil sample ...:. -_.just above..or.at the water table. _. 11 At eachsample depth, the drive sampler is driven 18 inches ahead of the drill augers into undis t curbed Sol- l. 'l�+pically ager the sampler is opened,either the lowermost or middle sample liner is . retrieved,and.the ends of the tube covered with aluminum foil and sealed with plastic caps. The plastic caps are secured to the liner with tape. The soil-filled liner is labeled with the location, sample number,date,time,depth,sampler,and borehole number. The samples are placed in zip- lock bags and stored in a cooler containing ice. e42171050/nov/apa A-1 33