ARCHIVED REPORTS_XR0012587 - Laserfiche WebLink

Home Browse Search

4y� aC."�- � � .. %� V �-htd �„.4y�;#: F� �. �, _ `l�•;'1� 4 S ' 3 �� .Y — a� Analyze vadose zone soil samples from the above boring for TPHG and BTEX. Prepar,. a Preliminary Site Assessment Report (PSAR). Details of the proposed scope of work are presented below. 2.2.1 Overexcavation of Contaminated Soil TPE proposes to conduct horizontal excavation of contaminated vadose zone soil to a distance of about 2 feet to 15 feet outward from the present position of the sidewalls and vertical excavation to a depth of about 12 feet if using a backhoe or to . Overexcavation will not be conducted a depth of about 25 feet if using an excavator to the extent of endangering buildings, sidewalk areas, utilities, or any other structures or objects. If, after excavating to the above limits, soil contamination is still present in the walls andlor floor of the excavation, TPE may advise the client to conduct soil borings as a second phase of remedial investigation to assess whether other remedial options, such as vapor extraction, may be more economical. All excavated soil will be stockpiled on site by placing the soil on a surface of asphalt or plastic to prevent cross contamination to the underlying surface and covering the soil with plastic. The extent of overexcavation will be based on the presence of apparent soil contamination as evidenced by visible hydrocarbon stains and odors, and by field screening (by head-space analysis) of excavated floor and sidewall soil samples for volatile organic compounds using a Gastech Inc. Trace-Techtor. 2.2.2 Verification Soil Sampling When the horizontal and vertical extent of contaminated vadose zone soil has been reached, based on the above parameters, or the horizontal and vertical limits discussed above have- been reached; - verification.....soil .samples will be collected for chemical 3