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PROCEDURES FOR CONT INATED SOILS <br /> If contaminated soils are encountered during the removal of the underground tank, there are two <br /> procedures to be considered. <br /> Option A. Over-Excavation During Tank Removal <br /> If the amount of contaminated soil appears to be small, generally less than 100 yards, it may be <br /> excavated immediately following the tank removal and tank soil sampling. The stockpile will be <br /> analyzed with a 4-tube composite sample per approximately 50 yards of soil to evaluate disposal, <br /> requirements. The soil will be covered with visqueen. <br /> Option A Closure of Tank Site <br /> If the amount of contaminated soil appears to be significant or the client does not wish to remove <br /> it on the day of the tank removal, the excavation will be backfilled using the excavated soil. The <br /> bottom of the excavation is filled with gravel as replacement of the tank volume and the gravel is <br /> covered with plastic sheeting to prevent migration of contaminated soil into the rock. The <br /> contaminated soil is then placed back in the excavation and compacted. The excavation is <br /> restored to grade and the site is cleaned up. Further characterization of the site would be required <br /> after the submittal of the site characterization work plan to the regulator in charge of this site. <br /> SITE INVESTIGA TION AND CHARACTERIZATION <br /> In general, an effort will be made to remediate any contamination that may be present during the <br /> tank removal. If this is not possible the site will be closed to prevent any safety issues at the site, <br /> and a work plan will be prepared for the necessary site investigation and characterization. <br /> PROCEDURES FOR CONTAMINATED WATER <br /> There are two procedures for evaluating the groundwater at this site. <br /> Option A. Pumping Prior to Sampling <br /> If groundwater is encountered in the excavation and appears to be impacted with hydrocarbons, <br /> one pit volume of groundwater may be pumped into a holding tank prior to collecting a water <br /> sample. The water in the pit and holding tank will be analyzed. <br /> Option B. Sampling Only <br /> If groundwater is encountered in the excavation and appears to be impacted with hydrocarbons, <br /> or its condition is uncertain, the necessary water samples will be collected prior to closing the <br /> excavation. <br />