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PANOCHE BURN SITE REMEDIATION volatile organic, in AS-2, GIS—1, GIS-2, and GIS-3 also links this analyte. The varying concentrations of hydrocarbons, volatile organics, and semi-volatile organics between GIS-1 and GIS-2/GIS-3 were due to the sampling location and time. GIS-1 was taken on November 11, 1996, in a lightly stained area, while GIS-2 and GIS-3 were taken on November 20, 1996, after discovering the gravel lenses of pyrolytic oil. The encapsulated ash at the site is considered hazardous because the analyses showed zinc exceeds the DTSC TTLC limit of 5,000 mg/kg and the STLC limit of 250 mg/L. Addition- ally, the ash exceeds the STLC limit for cobalt and lead. No federal hazardous waste criteria were examined. As ash and contaminated material were removed from the bottom area of the canyon, the electrical conductivity decreased from 52,600 to 921 µmhos/cm, TDS from 71,000 to less than 100 mg/L, and sulfate anions from 42,300 to 29 mg/L. Surface water results indicated all concentrations were below their maximum contaminant level for water. A comparison of the water results to background level could not be performed because the CIWMB engineer did not sample surface water above the encapsulated area. 3.4.5 Conclusions The tire fire produced large quantities of pyrolytic char, oil, and gas. The ash and oil-stained soils samples revealed the site was hazardous in accordance with the California Code of Regulations, Title 22, Section 66261.10, et seq. The confirmation soil sample analyses from both the CIWMB and the U.S. EPA show that the burn ash and contaminated soil were suc- cessfully removed and consolidated into the designated area. Where contaminated soil (i.e., gravel lenses) remained on the side slopes, a clay plug, HDPE liner, and clay cap were placed to protect the integrity of the project. The limited water results indicate the zinc and pyrolytic oil from the fire had not yet reached the surface waters. However, the water results are insufficient to conclude the remediation has prevented a release. All of the sampling results were within plausibility except for the metal analysis in the pyrolytic oil samples GIS-1 through GIS-3. Zinc concentrations in these samples were reported at 37, 46, and 47 mg/kg, respectively. The ash samples on surface indicated zinc concentrations from 32,800 to 156,000 mg/kg. With the hydrocarbon results ranging from 18,000 to 73,000 mg/kg, the CIWMB engineer expected the oil to transport the zinc into the gravel lenses below the surface. However, the results indicated the zinc and other metals were only at the surface. These low zinc levels in the oil may indicate zinc is not initially released during a fire or zinc is not soluble in oil. To further characterize the ash and pyrolytic oil samples, EPA Method 8280 for dioxins and furans should be added to ash analysis and EPA Method 8010 for halogenated volatile organics should be added to the pyrolytic oil analyses. CIWMB 31