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r' QIP. Mr Jeff'Wong Page 3 of 4 4.0 OTHER SITE ACTIVITIES A new water supply well was installed by Clark Well, Inc in October 2001 The well was installed and developed between October 11, 2001 and October 24, 2001 The well was installed near the southeast comer of the property, approximately 160 feet east of the existing water supply well The new well was drilled to a depth of approximately 395 feet below ground surface (bgs), with the well screen placed from approximately 335 to 395 feet bgs The annular well seal extends to a depth of 270 feet bgs This depth was selected based upon the lithology and a down-hole electric log conducted by Dewey Data Logging Services The completion of the well head, including concrete pad, pressure tank, fencing, and piping/electrical was supervised by Clark Well, Inc We anticipate that the new well will pass water quality testing in the near future and the existing water supply well will be destroyed 5.0 SUMMARY Groundwater levels in the shallow aquifer fell an average of 0 41 feet between August 2001 and November 2001 Groundwater flow beneath the site was largely influenced by an apparent groundwater depression near well MW4 Free product was observed in well MWI As an interim remedial effort, approximately 38 gallons of • product/water mixture has been removed and contained on site since August 16, 2001 A Ground Zero technician is periodically bailing free product from well MW 1 Since the last sampling round in August 2001, MTBE concentrations decreased in wells MW2 and MW4 but increased in wells MW3, MW5, and MW6 Benzene concentrations decreased in wells MW4 and MW7 and increased in wells MW2, MW3 and MW6 over the same period No MTBE was detected in wells MW7, MW8, or MW9(B) No benzene was detected in wells MW5, MW7, MW8 or MW9(B) Time versus concentration plots of constituents of concern (TPHg, benzene, MTBE) in site wells are included in Attachment C 6.0 CONCLUSIONS The lateral extent of benzene and TPHg contamination in groundwater beneath the site has essentially been defined, except for south and west of well MW2 The lateral extent of MTBE contamination beneath the site has been defined in all directions except north of well MW6 The apparent groundwater depression near well MW4 may be a result of facility well operation or an indicator that some vertical leakage of the shallow aquifer is occurring through the water supply well Based upon the absence of TPHg, benzene, and MTBE in well MW913, dissolved contamination in the upper water-beanng zone does not appear to extend into deeper zones It should be noted, however, that very low levels of toluene, ethylbenzene, and/or xylenes had been detected in well MW9(B) between February and August 2001 G\DaLi%GRO=ZEITULHBURG1Repurts\QMR14QM2(101 doc