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Emergency Remediation 2480 Tracy Blvd., Tracy, CA. • Page 16 Westates loaded the spent carbon for transport to Parker, Arizona on May 29, 1996. There it will be purged of all components of gasoline or any other contaminants present, reactivated, and recycled in beneficial use. Soil Treatment After evaluating the results of the analyses of soil sample TP-1 and TP-2 that were recovered from the basement excavation, in consultation with the staff of the SJCPHS, it was concluded that the contaminated soil would be treated by on-site aeration. Following treatment it would be recycled in beneficial use as engineered fill to raise the elevation of ' the previously-graded site to comport with the new floor elevations that required to conform to the revised elevation of the basement slab. To reduce delay and cost overruns consequent upon the contamination affecting the subsurface to a practical minimum, it was also decided that as much of the surface of the site as possible would be used to treat the soil, while, whenever such accommodation could be made, permitting the general contractor to proceed with work on the critical path of the construction project. With the concurrence of the SJCPHS, it was father decided that the goal for the aeration treatment would be to reduce concentrations of components of gasoline in the soil to as low a level as would be found practical without causing unwarranted delay to the construction contractor's work. This decision was justifiable because, even after minimal treatment by aeration, any hydrocarbons remaining in the fuel were expected to be at either negligible or very low concentrations of little regulatory concern. In addition, none of the affected soil would be removed from the site and the continuous concrete floor slabs and paving, that will cover essentially all of the property when construction is complete, will serve as an impermeable cap that will prevent any rain or other water falling onto the paving from coming into contact with any of the treated material. Before soil treatment work was begun, a grid was set out over the whole area of the site to provide for identification, control, and management of the soil undergoing treatment. The lines of this grid were 35 ft. apart and were located by flags set in the temporary fencing around the perimeter of the site. The sub-areas of the grid were identified by the letters A through 1, starting with A at the eastern fence of the site and progressing in alphabetical order to the west, and the numbers 1 through 5, starting at the north fence and increasing to the south. The layout of the grid is shown on Figure 5. Contaminated soil that was removed from the stockpile along the east side of the site in a total of five batches. The size of each batch was dictated by the area of the site currently available for soil-treatment operations and that could be used without hindering essential work to maintain progress with the construction of the car-wash and lubrication-service facility.