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then backfilled with imported clean fill. During the time when the excavation was left open, the site was secured with temporary fencing. Upon arrival at the site, a 30 X 25 foot area centered on the impacted area at the northern end of the former tanks as defined by the earlier Site Assessment sampling was outlined. An excavator was used to excavate this area. A dump truck periodically transported contaminated soil to the designated remediation.cell at the eastern end of the property. An AGI geologist monitored the progress of the operation by collecting frequent grab samples for testing for the presence of volatile hydrocarbons using a Flame ionization detector (FID). The samples were placed in a mason jar and after a short time the instrument probe -was' inserted to obtain a headspace reading. By this method expansion of the excavation was controlled and clean soils were segregated from impacted soils. The up fe®t-of.soil excavated consisted-of_.uncontaminated,rlarla#ive soil,and.loose sandy`filVmaterial'-This niatenal.was_s ockpiled-on-the soutllw__e__stern_ _portio_nof they excavatedYsite-and-.segregated-awayfrom-the impacted.soil. .A The contaminated soil mass was encountered at approximately 5 feet. The excavation was subsequently carried to 35 feet where field measurements indicated all significantly impacted soils were removed. Laterally, contaminated soils were confined to a 35 X 31 foot area. The location of the excavation relative to other site features and the aerial limits of impacted soils is shown on the Exhibit 2. A.plot plan and a three dimensional representation of the completed excavation is provided on ;Exhibit 3. Volumetric calculation��indicated thatY840Ycubic=yards o"f co taminated�so was-excavated.-�lri-addit on-to the_unimpacted.soil st_ockp}led on-site,-supplemenWI - -- clean.fill'in:the amount of.800 yards was-required to.backfill-theiexcavation 5.0 CONFIRMATION SAMPLING AND ANALYTICAL RESULTS Confirmation samples were collected, one from each wall of the excavation at varying depths dependent on accessibility by excavator. A bottom sample was also obtained from the center of the pit at a depth of 35 feet. Sample locations are depicted on the Excavation Plot Plan Exhibit 3. Samples were collected in brass sleeves from the excavator bucket, close to the teeth to insure that relatively undisturbed samples were taken. The samples were .immediately sealed with taped teflon-lined caps, labeled and placed in a cooler for later transport to the Smith Emery Company, a State of California certified laboratory` under chain of custody control. The samples were analyzed for the aromatic components benzene, toluene, ethylbenzene and xylenes (BTEX) and Total Petroleum Hydrocarbons as diesel (TPHd). Laboratory results are 4 listed in Table 1 and complete laboratory results are provided in Appendix A. No hydrocarbon concentrations were detected. The results demonstrate that all --impacted soils were removed by the excavation. t 5,of 7 .