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pressure gage is a limiting factor in the accuracy of the water level reading <br />(commonly limited to +/-1 PSI equivalent to +/- 2.31 feet of water). <br />Sonic Meter <br />To obtain a water level measurement using a sonic meter, one needs to open the <br />well to allow for a well measurement, measure or estimate the borehole <br />temperature and input this into the meter, create a seal around the surface of <br />well to facilitate a good signal response, select the sounding depth range <br />depending on expected water level depth, and take reading. <br />Pros: Process is very quick, is non-obtrusive, works for large depth range (25' to <br />1500'). <br />Cons: Obstructions in the well can cause erroneous readings; borehole <br />temperature estimates and setting the sounding depth may lead to inaccurate <br />readings. <br />Water Level Conductivity Meter <br />To obtain a water level measurement using a conductivity meter, one needs to <br />open the well to allow for a well measurement, disinfect the probe, lower the <br />conductivity probe into the well until a 'beep' is heard indicating that water has <br />been encountered, and retrieve the probe. A water level is recorded by reading <br />the graduated tape attached to the probe at a specified measuring point when a <br />beep is emitted by the meter. A conductivity meter has a smaller depth range <br />than the M-scope. <br />Pros: Graduated tape is accurate to 0.01', provides clear indication of water level. <br />Cons: Many wells do not have large enough access ports for the probe; probe <br />may become tangled with electrical wires while being lowered in well; time <br />intensive process to deploy and retrieve in deep wells; may require two people to <br />operate in deep well; requires disinfection; limited to depth of cable attached to <br />the probe. (The range of the conductivity meter used is 200 feet.) <br />2.2 Water Level Measurement Solicitation <br />The second part of the water level collection program is to contact the entities where water <br />levels are typically solicited by the State. Of the 120 wells identified as candidates, 30 wells <br />have water levels that are typically solicited. These 30 wells are owned by 12 different entities. <br />Each of the entities was contacted by phone followed by an email or letter describing the SPDSS <br />project and requests were made to obtain water level measurement data collected during the <br />October-December time period. <br />3.0 Results <br />This section presents the results of the autumn water level data collection. As discussed in <br />Section 2.0, the data collection effort was conducted in two parts, water level measurements and <br />water level data solicitation. <br />