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I i v I ' I . 23 Apri12002 , AGE NC Protect No 98-0521' Page 2 of 7 I ' The soil boring data indicates that silt underlies'the site to asdepth of approximately 15 feet below surface grade (bsg) and in turn is underlain by a silty sand at depths between 15 and 20 feet bsg Current ground water monitoring data at the site indicates that ground water occurs at a depth of approximately 8 feet bsg, historically, ground water flow direction has been toward the northeast ` 1 ' 3.0. GROUND WATER EXTRACTION FEASIBILITY TESTS An 8-hour step draw-down ground water extraction test and a 36-hour constant rate groundwater 1 extraction feasibility test was performed at the site on 22 January 2002, and 04 and 05 February 2002, respectively, to determine the feasibility of ground water extraction as a remediation ' alternative for the site Ground water monitoring well MW-2 was utilized as the extraction well ' Monitoring wells MWA through MW-4 were utilized as observation points Due to the limited number of permanent observation points at the site, temporary observations wells OW-1 through OW-4 were installed utilizing"direct-push"techniques and utilized as observation points Table 1 ' summarizes well construction specifications All observation wells were located cross- or up- gradient Purged ground water generated during the 8-hour step draw-down test was containenzed in an on- site 6,500-gallon poly tank,purged water generated during the constant rate ground water extraction test was containerized in two on-site 6,500-gallon poly tank ' I ' I F 1 S 3 1 8-HOUR STEP DRAW-DOWN PUMPING TEST , Prior to initiation of the'test, the ldepth-to-ground water was measured in the extraction well MW-2 and in observation wells MW-1,MW-3,MW-4 and OW-1 through OW-4 using a Solinst waterNlevel meter During the pumping test,depth to water was measured in the extraction and observation Wvells' z at approximately 30-minute` intervals Additionally, 7/8-inch diameter, model 3001 Solinst ' Levclogger pressure transducers were deployed in wellsIMW-2, OW-1, OW-2 and',OW-3 Each ` } pressure transducer was preprogrammed prior to the pumping test to log water levels at one'-minute intervals' Copies of field logs are included in'Appendix A a The pumping test consisted of extracting ground,water`from extraction well MW-2 utilizing a 4-inch r' ! ' diameter submersible Grundfos Redi-flo pump umping began atone gallon per minute(gpm),after 175 minutes, pumping rate was increased,to three gpm 'The pumping rate was increased to four t 4` gpm'after approximately 325 minutes of pumping Approximately 1,600 gallons of water were IE 1 extracted from M4-2 during the eight-hour test ' 1 Advanced GeoEnvironmental,inc t�I