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APPENDIX A <br /> FIELD PROTOCOL <br />' The static water level and floating product level, if present, in each well that contained <br /> water was measured with an ORS Interphase Probe Model No 1068018 or Solonist <br /> Water Level Indicator, these instruments are accurate to the nearest 0 01 foot These <br /> groundwater depths were subtracted from wellhead elevations, including corrections for <br /> product thickness, when necessary, for gradient evaluation by multiplying product <br /> thickness (PT) by a correction factor 0 8 and subtracting from the DTW (Adjusted DTW <br /> = DTW - [PT x081) <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 <br /> interface (if possible) and collecting a sample from near the surface of the water in the <br />' well The samples were checked for measurable floating hydrocarbon product All <br /> Teflon° bailers are triple washed with Alconox°and triple rinsed with distilled water prior <br /> to use <br /> Before water samples were collected from the groundwater Monitoring Wells, the wells <br /> were purged until stabilization of the temperature, pH, and conductivity were obtained <br /> Approximately four well casing volumes were purged before those characteristics <br /> stabilized The quantity of water purged from each well was calculated as follows <br /> One well casing volume = rrrzh(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 <br /> removed <br /> rAfter purging, each well was allowed to recharge to at least 80% of the initial water <br /> level Water samples were collected with a new disposable or Teflon° bailer, and <br /> carefully poured into 40-milliliter (ml) glass vials, which were filled so as to produce a <br /> positive meniscus Each vial was preserved with hydrochloric acid, sealed with a cap <br /> containing a Teflon° septum, and subsequently examined for air bubbles to avoid <br /> headspace which would allow volatilization to occur The samples were promptly <br /> transported in iced storage in a thermally-insulated ice chest, accompanied by a Chain <br /> of Custody Record, to a California-certified laboratory <br /> 1 • <br /> MNAw 194 2611gw morntlanl gwmr apa{Aug 18 951 S H <br /> r <br />