COMPLIANCE INFO_2001-2005 - Laserfiche WebLink

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2.0 UST Removal Field Activities 2.1 Tank Removal On October 1, 2001, TAIT began excavation activities by removing the concrete pad that covered the tank. The fuel conveyance piping was then disconnected from the UST and the building. The piping was observed to be in good condition without any holes or cracks. Fill material around the tank was excavated and placed on plastic adjacent to the tank excavation. No soil discoloration or petroleum hydrocarbon odors were observed during excavation activities. Groundwater was not encountered in the piping excavation. On October 3,2001,the UST was triple rinsed by Ecology Control Industries(ECI)personnel. The rinsing was completed using a fresh water/detergent mixture and a hot water pressure washer. Visual inspection of the tank did not indicate any residual sludge or liquid on the visible portions of the interior of the tank. Approximately 700 gallons of rinsate was removed from the tank using a vacuum truck. Following completion of the triple-rinse activities,the internal atmosphere of the tank was inerted with approximately 150 pounds of dry ice. Time was allowed for the dry ice to displace residual vapors from the tank before measuring the percent of the lower explosive limit and percent oxygen within the tank. Under the authorization of Ms. Michelle Sterni-Le of the SJCPHS-EHD,the tank was removed from the excavation and prepared for off-site disposal. Upon removal,the tank was scraped of exterior soil and inspected for signs of deterioration, holes, or leakage. No holes, cracks, or other indications of leakage were observed on the tank. No soil discoloration or petroleum hydrocarbon odors were noted in the excavation, and no groundwater was present. Following inspection,the tank was loaded onto a flat-bed truck and transported for disposal by ECI to their facility in Richmond, California. The tank was transported as hazardous waste under Manifest No. 21086335. A copy of the manifest and certificate of destruction for transport and disposal of the tank is presented in Appendix B. 2.2 Sampling Activities On October 3,2001,two soil samples were collected from the tank excavation under the direction and supervision of Ms.Michelle Sterni-Le of the SJCPHS-EHD. Due to equipment limitations and surrounding concrete,the soil samples were both collected from each end of the tank excavation along the east sidewall. Soil samples PB-1(12') and PB-2(12')were collected CNCD\10-30-01\0:SHAIMUST101-0076.doc 2