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1 23 March 2001 AGE-NC Project No 97-0301 Page 3 of 11 2 2 EQUIPMENT DECONTAMINATION The hollow stem augers were steam cleaned prior to each bore hole advancement Sampling tools and brass sleeves used for sample collection were thoroughly washed with a solution of Alconox, and were thoroughly rinsed with clean tap water pnor to each sampling sequence Following drilling activities, nnseate generated from decontaminating the equipment was placed in properly labeled ' DOT-approved model 17H 55-gallon drums and was stored on-site in an area lacking public access 23 SAMPLE LOGGING During drilling activities, soil sample duplicates were monitored for the presence of organic vapor using an organic vapor meter equipped with a photo-ionization detector (PID Thermo Environmental 580A, 10 0 eV,calibrated to isobutylene)and were visually described on boring logs in accordance with the Unified Soil Classification System (USCS) Boring logs from MW-5,MW-6 and MW-7 are included as Appendix A General lithology beneath the site is depicted in cross sectional views A-A', B-B'and C-C'on Figures 3, 4 and 5, respectively 2 4 MONITORING WELL COMPLETION Soil bonngs MW-5, MW-6 and MW-7 were single-completed as ground water monitoring wells utilizing 2-inch diameter, schedule 40, blank polyvinylchlonde (PVC) well casing and perforated, 2-inch diameter PVC well casing (0 010-inch slot) Each well was installed by placing a PVC well casing assembly through the hollow stem of the augers to the total depth of the boring The augers were incrementally raised as No 2112 Lonestar Lapis Luster sand(filter pack)was slowly poured down the annulus between the well casing and the inner wall of the hollow stem auger The filter pack was placed adjacent to the screened casing from ' the bottom of the boring to a point approximately two feet above the top of the screen, following filter pack placement, a surge block was inserted into the well °casing and was alternately raised and lowered (surged) repeatedly for approximately 20 minutes Approximately three feet of bentonite chips (annular seal)were placed above the filter pack and were hydrated with clean tap water The remaining annular space was backfilled with portland cement(grout seal) As-built monitoring well- construction diagrams are included as Figures 6, 7 and 8 25 SURVEYING OF MONITORING WELLS On 01 February 2001 a California state-licensed survey engineer from Baumbach & Piazza, Inc Advanced GcoEnvironmental,Inc