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lowered to a point dust below the liquid level, retrieved, and observed for floating hydrocarbon Liquid measurements were recorded to the nearest 0 01 foot in the Depth to Water/Floating Product Survey Form The groundwater elevation at each monitoring well was calculated by subtracting the measured depth to water from the surveyed elevation of the top of the well casing (Every attempt was made to measure depth to water for all wells on the same day ) Total well depth was then measured by lowering the sensor to the bottom of the well Total well depth, used to calculate purge volumes and to determine whether the well screen was partially obstructed by silt, was recorded to the nearest 0 1 foot on the Depth to Water/Floating Product Survey Form Well Purging Before sampling occurred, a polyvinyl chloride (PVC) banter, centrifugal pump, low-flow submersible pump, or Teflon banter was used to purge standing water in the casing and gravel pack from the monitoring well Monitoring wells were purged according to the protocol presented in Figure A-1 In most monitoring wells, the amount of water purged before sampling was greater than or equal to three casing volumes Some monitoring wells were expected to be evacuated to dryness after removing fewer than three casing volumes These low-yield monitoring wells were allowed to recharge to a level sufficient for sample collection If insufficient water recharged after 24 hours, the monitoring well was recorded as dry for the sampling event Groundwater purged from the monitoring wells was transported in a 500-gallon water trailer, 55-gallon drum, or a 325-gallon truck mounted tank to EMCON's San Jose or Sacramento office location for temporary storage EMCON arranged for transport and disposal of the purged groundwater through Integrated Stream Management, Inc Field measurements of pH, specific conductance and temperature were recorded in a waterproof field logbook Figure A-2 shows an example of the Water Sample Field Data Sheet on which field data are recorded Field data sheets were reviewed for completeness by the sampling coordinator after the sampling event was completed The pH, specific conductance, and temperature meter were calibrated each day before field activities were begun The calibration was checked once each day to verify meter performance Field meter calibrations were recorded on the Water Sample Field Data Sheet Well Sampling • A Teflon bailer was the only equipment acceptable for well sampling When samples for volatile organic analysis were being collected, the flow of groundwater from the bailer was regulated to minimize turbulence and aeration GIass bottles of at least 40-milliliters SACINIP70108OW8051470IAN-94\dms 1 A-4