Laserfiche WebLink
k4 KLEINFELDER <br /> i, <br /> r A-3.3 Equipment Decontamination <br /> 1 To reduce the potential for cross-contamination between wells, developing equipment is <br /> washed in a trisodium phosphate or non-phosphate detergent solution and rinsed in <br /> distilled water or steam cleaned prior to use in the next monitoring well. <br /> A-3.4 Well Suivey <br /> j The locations of soil borings and monitoring wells, and the elevation of the top of the <br /> PVC casings are usually surveyed and tied into permanent markers, if readily available. <br /> Survey accuracy is 0.1 foot for the "x" and "y" coordinates and .01 foot for the 'Y' <br /> coordinate. The depth to static groundwater is measured from a set location at the top <br /> of the PVC casing (usually the north rim). The depth of water is then subtracted from <br /> the elevation of the top of the well casing to provide a groundwater elevation for each <br /> monitoring well location. <br /> A-4 GROUNDWATER MONITORING <br /> A-4.1 Water Level Measurements <br /> Water level measurements are made in the wells prior to purging and sampling the <br /> wells. Measurement protocol is as follows: <br /> 1. Prior to obtaining water level measurements, the monitoring wells would be <br /> opened and allowed to equilibrate for a period of approximately Y2 hour. <br /> 2. The water level probe is decontaminated in a trisodium phosphate or non- <br /> phosphate detergent wash, followed by a distilled water rinse, prior to use in <br /> each well. <br /> 3. Water level measurements are made using a conductivity-based water-level <br /> meter. Depth-to-water is generally measured from a surveyed mark on the north <br /> rim of the PVC well casing. <br /> i The water level measurements are converted to elevations using the surveyed casing <br /> l elevations. <br /> A-4.2 Groundwater Sampling <br /> Groundwater samples are collected from the monitoring wells at the site. The sampling <br /> protocol for each well is as follows: <br /> 1. Down-well equipment (pumps, bailers, etc.) is decontaminated by steam <br /> cleaning, or by scrubbing in a trisodium-phosphate or non-phosphate detergent <br /> wash followed by a distilled water rinse, prior to use in each well. Bailer cord is <br /> replaced prior to use in each well. <br /> 7 <br /> l 12280.MONIST05R8031JZ:ly Page A-5 <br /> y ©2005, Kleinfelder, Inc. July 25, 2005 <br /> I <br />