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Working to Restore Nature <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 Solomst Water <br /> Level Indicator, these instruments are accurate to the nearest 0 01 foot These groundwater <br />' depths were subtracted from wellhead elevations,including corrections for product thickness, <br /> when necessary, for gradient evaluation by multiplying product thickness (PT) by a <br /> correction factor 0 8 and subtracting from the DTW (Adjusted DTV = 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 <br />' interface (if possible) and collecting a sample from near the surface of the water in the well <br /> The samples were checked for measurable floating hydrocarbon product. All Teflon® <br /> bailers are triple washed with Alconox® and triple rinsed with distilled water prior to use <br />' Before water samples were collected from the groundwater moratoring wells, the wells were <br /> purged until stabilization of the temperature, pH, and conductivity were obtained <br /> Approximately four well casing volumes were purged before those characteristics stabilized <br /> The quantity of water purged from each well was calculated as follows <br /> 1 well casing volume = -irrzh(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 /> 748 = conversion constant from cubic feet to <br /> 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 <br /> Each vial was preserved with hydrochloric acid, sealed with a cap containing a Teflon® <br /> septum, and subsequently examined for air bubbles to avoid headspace which would allow <br /> volatilization to occur The samples were promptly transported in iced storage in a <br /> thermally-insulated ice chest, accompanied by a Chain of Custody Record, to a California- <br /> certified laboratory <br /> r <br /> 013293/014 <br /> _ 7:�7 - W-- <br />