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AW M�AE�" � <br /> i Working to Restore Nature <br /> FIELD PROTOCOL <br /> The static water level and floating product level, if present, in each well that contained water <br />' was measured with an ORS Interphase Probe Model No. 1068018 or Solonist Water Level <br /> Indicator; these instruments are accurate to the nearest 0 01 foot These groundwater depths <br /> were subtracted from wellhead elevations, including corrections for product thickness, when <br /> necessary, for gradient evaluation by multiplying product thickness (PT) by a correction factor <br /> 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 <br /> approximately half the length of a new disposable or Teflon® bailer past the air-water interface <br /> (if possible) and collecting a sample from near the surface of the water in the well The <br />' samples were checked for measurable floating hydrocarbon product. All Teflon® bailers are <br /> triple washed with Alconox8 and triple nnsed with distilled water prior to use <br /> Before water samples were collected from the groundwater monitoring wells, the wells were <br /> purged until stabilization of the temperature, pH, and conductivity were obtained <br /> Approximately three 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 = zzr2h(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 = welI casing volumes removed <br />' After purging, each well was allowed to recharge to at least 80%fl of the initial. water g ate level <br /> Water samples were collected with a new disposable or Teflon® bailer, and carefully poured <br />' into 40-milliliter (mI) 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 Teflono <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 thermally- <br /> insulated ice chest, accompanied by a Chain of Custody Record, to a California-certified <br /> laboratory <br /> F7132 931Q14 <br /> I <br />