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• BRIEF REVIEW OF LATEWORK PERFORMED On January 14 , 1994 , Osterberg & Stewart Drilling Co mobilized a C-57 auger rig on the Hammertown property, ( identified as TB-2 on the attached Plate A, ) using 5' lengths of 8 1/4" OD hollow-stem augers equipped with a 30" long California modified split-spoon sampler designed to hold 2 1/2" diameter metal tubes The bottom flight was equipped with a latching mechanism to enable lowering and retrieving the core barrel quickly The coring assembly was advanced by rotating and advancing the auger flights without the necessity of driving the core barrel into the soil with a drive hammer Soil samples were taken at 5 ' intervals from 20 ' to 71 ' bgl , they were screened with a PID meter, briefly described and promptly preserved for analysis . Using a hydropunch tool driven below the bottom of the soil boring, a groundwater sample was collected and properly preserved Both samples were transported to FGL Envi- ronmental and analyzed for BTEX & TPH--G All samples were below detection limits The auger hole was grouted to the surface with cement under the direction of a representative of the San Joaquin County EHD On January 17 , the same rig & crew were mobilized over TB-1 on the Normac parcel, (refer to Plate A for it ' s location ) The auger flights had been thoroughly decontaminated prior to arrival on site Using the same equipment and field procedures as described for TB-2 , cores were taken at 5 ' intervals from 21 ' to 71 ' bgl A groundwater sample was obtained by driving the hydro- punch tool to approximately 75' bgl The samples were properly preserved, transferred to FGL laboratory, and analyzed for BTEX & TPH-G All samples were below detection limits As a result of the above work, it has been determined that the limits of soil contamination have been fully defined, and ground water has not been impacted In order to verify that site closure is warranted, two additional test borings have been requested by the EHD, identified as "A" & "B' on the attached Plate A The following workplan is designed to accomplish that task WORKPLAN ME PLACING SOIL BORINGS TQSA SESS POSSIBLE RESIDUAL oN 9N TM NORMAC & HA=gTOWN pgORERTIES 1 Mobilize an Osterberg & Stewart auger rig equipped with clean hollow-stem auger flights & wireline operated soil sampling • device with a California modified split-spoon sampler Order of drilling will be determined after rig on location Work will be performed under previously approved permits 0001425 & #001426 2