REMOVAL_1993 - Laserfiche WebLink

Home Browse Search

U Sample Collection and Analysis 114W After removing the tanks on October 29, 1993, some additional excavation of soil adjacent to and below the tanks was conducted under the observation of PHS-EHD, after this minor overexcavation work four soil samples and one water sample were collected. The sample location, identification number, collection time and depth below top of concrete (parking lot) surface, were documented on each sample on a proper chain of custody. The samples were immediately capped and placed in a chilled ice chest for transportation to Sparger Technology, Inc. of Sacramento, a State certified analytical laboratory. As directed by Mr. Bill Snavely PHS-EHD, the soil samples from below Tank 1 were to be analyzed as if the tank last contained leaded gas. These analyses were for Total Petroleum Hydrocarbons as Gasoline (TPI-1-G), Benzene, 'toluene, Ethyl Benzene, and Xylene (BTEX), Total Lead (Pb), and Ethylene dibromide (EDB). Soil samples from the adjacent excavation sidewall to "Tank 2 and below Tank 3 were to be analyzed as an unknown fuel. These analyses were for TPI-I-G, Total Petroleum Hydrocarbons as Diesel (TPH-D), BTEX, Total Lead (Pb), and (EDB). Because 'yanks 4 and 5 were associated with Tanks 2 and 3 no discrete samples were taken. The soil from the spoils stockpile from the excavation were analyzed for T'I'11-G, 'TPI1-1), BTEX, 'Total Lead (Pb), EDB, CAM 17 Metals, and a 96 hour, three concentration fish bioassay. One water sample was collected from groundwater within the excavation adjacent to Tank 3. The groundwater sample was analyzed for TPH-G, TI'II-D, BTEX, and EDB. Enclosed in Appendix D is a copy of the Chain of Custody and the laboratory report for the collected samples. Excavation of Petroleum Impacted Soil During the tank removal process there was petroleum hydrocarbon stained soil contained within the sidewalls of the tank excavation. After consulting with Mr. Bill Snavely of PHS-EHD, this stained soil was remoNed until there was no visible signs and field screening with an Organic Vapor deter indicated there was no contamination remaining on the sidewalls of the excavation. 'the total depth of the excavation was approximately 9 feet below the reference point on the adjacent concrete surface and extended approximately 1.5 feet below the level of groundwater. The volume of the soil removed from the excavation was approximately 190 cubic yards. As identified in the tank closure application submitted to ITIS-EIID all soil removed from the excavations (property under the jurisdiction of the City of 'Tracy) was relocated to the Tracy Airport, land Treatment Facility ('UFF). The LT'F documents provided to Wright by The City of 'Tracy and conversations with City Staff indicated that non-hazardous soils could be treated at the LIT site. Backfill of Excavation On November 1, 1993 groundwater with a visible petroleum sheen that had infiltrated the excavation was removed using a Vacuum Truck. The volume removed was 3225 gallons, which was shipped to Petroleum Recycling Corp as non-RCRA Hazardous Waste for recycling as documented in the hazardous Waste Alanifest dated November 1, 1993 in Appendix B. At this time the excavated area was hackfilled to a level of 4.5 feet below the concrete lot surface t,;hh /4 inch crushed rock in 12 inch lifts. A Geotextile fabric layer was then placed over the gravel. on top of the Geotextile fabric a 2.5 foot layer of 3/4 Class 11 aggregate was placed and compacted in 8 inch. lifts. A compaction report b} the Cit,. el 'frac} is forthcoming. Lc,:zd tickets for the backfill materials and the Backfill Excavation Certificate is enclosed in Appendix E. 2