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Jun 22 01 10:38a 06/18/01 NON 17:38 FAX is015 B-3.4 Well Survey The locations of soil horings and monitoring wells, and the elevation of the top of the PVC casings an usually surveyed and tied into permanent markcrs, if readily available. Survey accuracy is 0. 1 foot for the 'Y' and *y" coordinates and 01 fo*t for the "z" coordinate. The depth to static grourdwater is measured from a set location at the top of the PVC casing (usually the north rim)_ The depth of wateT is then subtracted from the elevation ofthe top of the well casing to provide a grwindwater elevation for each monitoring well location. B-4.1 Water Level Measurements Water level measurements are made in the weM prior to purging and sampling the wells, Measurement protocol is as follows - U=1 if k- , * 4 0 M V - 0 to 2. Water level measuremeats are made using a conductivity -based water --level meter. Depth -to -water is generally measured from a surveyed mark an the north rim of die PVC well casing. The water level measurements am converted to clevatioes using the surveyed casing clevatiom, Groundwater Sampling Groundwater samples we collected from the monitoring wells at the site. The sampling protoco., fA r each well is as follows: Down -well equipmerit (pumps, bailers, etc.) is decontaminatld by stearn clean-ing, or 'I scrubbing in a trisodiurn-phosphate or non -phosphate detergent wash followed by distilled waterrinse, prior to use in each well, Uler cord is replaced prior to, use in well. L 3. The volume of water in gallons standing in the well is calculated by subtraaing the depth to gToundwater measurement fmin die depth of the well and multiplying by the appropriate conversion factor (0- 16 for 2 -inch wells, and 0. 65 for 4 -inch wells). 4. Three to five well volumes of water we purged from each well using a submersible pump, bladder pump. or Teflon bailer. 20-YPI -61 U291 IF$ 63 fte OA CapyriShf 2001, Kkin&ldcr. Inc, June 14, 2001 p. 13