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FIELD PROTOCOL <br /> The static water level and floating product level, if present, in each well that contained water was measured with <br /> an ORS Interphase Probe Model No. 1068018 or Solonist Water Level Indicator; these instruments are accurate <br /> to the nearest 0.01 foot. These groundwater depths were subtracted from wellhead elevations, including <br /> corrections for product thickness, when necessary, for gradient evaluation by multiplying product thickness(PT) <br /> by a correction factor 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 approximately half the <br /> length of a new disposable or Teflon® bailer past the air-water interface (if possible) and collecting a sample <br /> from near the surface of the water in the well. The samples were checked for measurable floating hydrocarbon <br /> product. All Teflon®bailers are 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 purged until <br /> stabilization of the temperature, pH, and conductivity were obtained. Approximately three well casing volumes <br /> were purged before those characteristics stabilized. The quantity of water purged from each well was calculated <br /> as follows: <br /> 1 well casing volume=pi2h(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. Water samples were <br /> collected with a new disposable or Teflon®bailer, and carefully poured into 40-milliliter (ml) glass vials, which <br /> were filled so as to produce a positive meniscus. Each via] was preserved with hydrochloric acid, sealed with a <br /> cap containing a Teflon® septum, and subsequently examined for air bubbles to avoid headspace which would <br /> allow volatilization to 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 /> 1 <br />