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APPENDIX A <br /> C <br /> FIELD PROTOCOL <br /> The static water level and floating product level, if present, in each well that contained water <br /> was measured with an ORS Interphase Probe Model No 1068018 or Solonist Water Level <br /> Indicator, these instruments are accurate to the nearest 0 01 foot These groundwater depths <br /> were subtracted from wellhead elevations, including corrections for product thickness, when <br /> necessary, for gradient evaluation by multiplying product thickness (PT) by a correction factor <br /> 0 8 and subtracting from the DTW (Adjusted DTW = DTW-[PT x 0 8]) <br /> Water samples collected for subjective evaluation were collected by gently lowering <br /> approximately half the length of a new disposable or Teflon®bailer past the air-water interface <br /> (if possible) and collecting a sample from near the surface of the water in the well The <br /> samples were checked for measurable floating hydrocarbon product All Teflon® bailers are <br /> triple washed with Alconox@ and triple rinsed with distilled water prior to use <br /> Before water samples were collected from the groundwater Monitoring Wells, the wells were <br /> purged until stabilization of the temperature, pH, and conductivity were obtained <br /> Approximately three well casing volumes were purged before those characteristics stabilized <br /> The quantity of water purged from each well was calculated as follows <br /> One well casing volume = nr2h(7 48) where <br /> r = radius of the well casing in feet <br /> h = column of water in the well in feet <br /> (depth to bottom - depth to water) <br /> 7 48 = conversion constant from cubic feet to gallons <br /> Gallons of water purged/gallons in 1 well casing volume =well casing volumes removed <br /> After purging, each well was allowed to recharge to at least 80% of the initial water level <br /> Water samples were collected with a new disposable or Teflon® bailer, and carefully poured <br /> into 40-milliliter (ml) glass vials, which were filled so as to produce a positive meniscus Each <br /> vial was preserved with hydrochloric acid, sealed with a cap containing a Teflon® septum, and <br /> subsequently examined for air bubbles to avoid headspace which would allow volatilization to <br /> occur The samples were promptly transported in iced storage in a thermally-insulated ice <br /> chest, accompanied by a Chain of Custody Record, to a California-certified laboratory <br /> • <br /> M%A-194 2911gw mcn1nanl-pwmr apa[Apr 17 981 � H <br />