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S E C O R placed in the annular space across the entire screened interval, and extends approximately 1 to 2 feet above the top of the screen for the well. A bentonite and Portland cement seal extends from the sand pack to the ground surface. The boring logs show well construction details. Well Development and Surveying The wells were developed and sampled after completion. The development procedure for each well consists of pumping or bailing water from the well until the water was visibly clear, the well goes dry, or until a maximum of ten casing volumes have been removed. After development, water levels were allowed to partially recover. Groundwater samples were then collected using a disposable Teflon bailer, placed into appropriate EPA-approved containers, labeled, placed on ice, and transported to the laboratory accompanied by chain-of-custody documentation. A California State Licensed Surveyor surveyed the newly installed wells. The well casings were surveyed to the nearest 0.01 feet in elevation to a known benchmark. Organic Vapor Procedures Soil samples collected at 5-foot depth intervals during drilling were 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 involved measuring approximately 30 grams from an undisturbed soil sample, placing this subsample in a sealed container (either a zip-lock bag or a mason jar). The container was warmed for approximately 20 minutes (in the sun), then the head-space within was tested for total organic vapor, measured in parts per million as benzene (ppm; volume/volume). The instrument was calibrated prior to drilling using a 100-ppm isobutylene standard (in air) and a sensitivity factor of 55 which relates the photo-ionization potential of benzene to that of isobutyiene at 100 ppm. The results of the field testing were 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 Selected soil samples and groundwater samples collected were analyzed for total petroleum hydrocarbons as gasoline (TPHg), total petroleum hydrocarbons as diesel (TPHd), and total petroleum hydrocarbons as motor oil (TPHmo) by EPA Method 8015, and benzene, toluene, ethyl benzene, total xylenes (BTEX), methyl tertiary butyl ether (MtBE), tertiary butyl alcohol (TBA), di-isopropyl ether (DIPE), ethyl tertiary butyl ether (EtBE), tertiary amyl methyl ether (TAME), 1,2-dichlorothene (1,2- DCA), and ethylene dibromide (EDB) by EPA Method 8260. In addition, groundwater samples collected during monitoring well sampling were analyzed for methanol and ethanol. Soil Cuttings and Rinsate Water Sail cuttings generated during drilling operations were temporarily stored onsite on and covered with plastic sheeting pending characterization and disposal. Soil cuttings were removed by Chevron's disposal contractor to an appropriate disposal facility. Water generated during steam cleaning, and sampling of the borings was temporarily stored in DOT-approved 55-gallon drums pending transport by Chevron's disposal contractor to an appropriate disposal or treatment facility.