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i <br /> APPENDIX A <br /> FIELD PROTOCOL <br /> 1 �I <br /> The static water level and floating product level, if present, in each well that <br /> contained water was measured with an Interphase Probe or Water Level Indicator, <br /> these instruments are accurate to the nearest 0 01 foot These groundwater depths <br /> were subtracted from wellhead elevations, including corrections for product <br /> ' thickness, when necessary, for gradient evaluation by multiplying product thickness <br /> (PT) by a correction factor 0 8 and subtracting from the DTW (Adjusted DTW = <br /> DTW - [PTx081) <br /> 1 <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 <br /> the well The samples were checked for measurable floating hydrocarbon product <br /> All Teflon° bailers are triple washed with Alconox° and triple rinsed with distilled <br /> ' water prior to use <br /> Before water samples were collected from the groundwater monitoring wells, the <br /> wells were purged until stabilization of the temperature, pH, and conductivity were <br /> obtained Approximately three well casing volumes were purged before those <br /> characteristics stabilized The quantity of water purged from each well was <br /> calculated as follows <br /> 1 well casing volume = Tcrzh(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 /> ' <br /> 748 = conversion constant from cubic feet to <br /> gallons <br /> Gallons of water purged/gallons in 1 well casing volume = well casing volumes <br /> removed <br /> After 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 Teflonc, septum, and subsequently examined for air bubbles to avoid <br /> headspace which would allow volatilization to occur The samples were promptly <br /> LMVNw 594 2591quik 98 apa FOCI 30 971 <br />