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4 ORGANIC VAPOR PRESSURES Soil samples collected at 2-1/2 foot depth intervals during drilling and direct push will be analyzed in the field for ionizable organic compounds using a photo -ionization detector (PID) with a 10.2 eV lamp or a flame ionization detector (FID). The test procedure will involve measuring approximately 30 grams from an undisturbed soil sample, then placing this subsample in a sealed container (either a zip -lock bag or a mason jar). The container will be warmed in the sun for approximately 20 minutes and then the head - space within will be tested for total organic vapor, measured in parts per million as benzene (ppm; volume/volume). The instrument will be calibrated prior to drilling using a 100 ppm isobutylene standard (in air) and a sensitivity factor of 55 that relates the photo -ionization potential of benzene to that of isobutylene at 100 ppm. The results of the field-testing will be noted on the boring logs. PID and FID readings are useful for indicating relative levels of contamination, but cannot be used to evaluate hydrocarbon levels with the confidence of laboratory analyses. LABORATORY PROCEDURES Soil and groundwater samples from each direct -push boring will be submitted for chemical analysis. All soil and groundwater samples submitted for chemical analysis will be analyzed for Total Petroleum Hydrocarbons reported as gasoline (TPHg), diesel (TPHd), and motor oil (TPHmo) by EPA Method 8015M, and benzene, toluene, ethylbenzene, and total xylenes by EPA Method 8260B. A silica -gel clean-up will be performed on all samples submitted for analysis for TPHd and TPHmo. TPHd and TPHmo analyses will be performed on the samples before and after performing the silica -gel cleanup. In addition, all soil and groundwater samples will be analyzed for methyl tertiary butyl ether (MtBE), di -isopropyl ether (DIPE), tertiary amyl methyl ether (TAME), ethyl tertiary butyl ether (EtBE), tertiary butyl alcohol (TBA), ethyl dibromide (EDB), 1,2 dichloroethane (1,2 -DCA), ethanol, and methanol by EPA Method 8260. SOIL CUTTINGS AND RINSATE WATER Soil cuttings generated during drilling operations will be temporarily stored onsite on and covered with plastic sheeting pending characterization and disposal. Chevron's disposal contractor will remove soil cuttings to an appropriate disposal facility. Water generated during steam cleaning, and sampling of the borings will be temporarily stored in DOT - approved 55 -gallon drums pending transport by Chevron's disposal contractor to an appropriate disposal or treatment facility.