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APPENDIX A <br /> FIELD PROTOCOL <br /> The static water level and floating product level, if present, in each well that <br /> contained water was measured with an ORS Interphase Probe Model No. 1068018 <br /> or Solonist Water Level Indicator; these instruments are accurate to the nearest <br /> 0,01 foot. These groundwater depths were subtracted from wellhead elevations, <br /> including corrections for product thickness, when necessary, for gradient evaluation <br /> ' <br /> by multiplying product thickness (PT) by a correction factor 0.8 and subtracting from <br /> the DTW (Adjusted DTW = DTW - [PT x 0.8]). <br /> Water samples collected for subjective v <br /> P � e e aluatEon 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 <br /> ' 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 calculated <br /> as follows: <br /> ' 1 well casing volume = rrr2h(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 /> 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 <br /> a positive meniscus. Each vial was preserved with hydrochloric acid, sealed with a <br /> cap 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 /> 0 <br /> ' MV1w:W4.273W-qtrapt[Jon 24,961 ��� <br />