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31 January 1997 AGE-NC Project No 95-0125 Page 4 of 7 below surface grade A total of eleven soil samples were collected from the sidewalls and floor of the excavation, under the direction of Ms Margaret Lagono of the PHS-EHD TPH-g was detected in soil samples collected from the sidewalls of the excavation at concentrations as high as 1,600 parts per million(ppm, reported as milligrams per kilogram, sample 7-East) Toluene, ethylbenzene and xylenes were detected in excavation soil samples at concentrations ranging from 0 0072 ppm (toluene, 3-East) to 100 ppm (xylenes, 7-East) Benzene was not detected in any of the samples collected Under the authorization of the PHS-EHD, approximately 44 tons (32 cubic yards) of pea gravel and crushed rock were placed on the bottom of the excavation The pea gravel and crushed rock was used to fill the excavation above the free standing water in the excavation The excavation I was then backfilled using approximately 240 cubic yards of clean fill sand, and 14 cubic yards of gravel were used to cover the excavation Results of the excavation were detailed in AGE Quarterly Repot t, dated 26 February 1996 26 SOIL STOCKPILE AND PURGE WATER SAMPLING Stockpiled soil was sampled by representatives of AGE on 05 January 1996 Four samples were collected from the stockpiled soil and from containerized purged water stored on-site TPH-g was detected in stockpiled soil samples at concentrations as high as 480 ppm (SP3) BTE&X were detected 3n stockpiled soil samples at concentrations as high as 13 ppm (xylene, SP2) Hydrocarbons were not detected in water samples collected from the containerized purged water Results of the sampling were detailed in the above-mentioned AGE Quat tet ly Report, dated 26 February 1996 3.0. PROCEDURES 3 1 MONITORING WELL PURGE PROCEDURES On 05 November 1996, the depth to ground water to all wells was measured relative to the casing tops using a Solinst water level meter The relative ground water elevation in each well and prevailing hydraulic gradient were determined from these data Ground water depth data is presented in Table I- Relative Ground Water Elevations After depth to water measurements were performed, a pre-cleaned bailer or submersible pump was used to remove approximately eight to twelve gallons of standing water from monitoring wells MW- 1, MW-5, MW-6 , MW-7, MW-8, MW-9 and MW-10 A pre-cleaned PVC bailer was used to remove approximately one-half of a gallon of standing water from MW-2 T stabilization parameters, 1 temperature,pH and conductivity, were measured at regular intervals in each purged well using an ICM Water Analyzer Purged water was stored on-site in DOT drums Ground water stabilization and field data sheets are included in Appendix A