Rising head slug test reference point

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Measuring Groundwater Discharge: Rising Head Slug Test

We will estimate the specific discharge of the aquifer (water flux per unit area per unit time). We will use a modified version of Darcy's Law , which states:

1. Measure the ``static'' depth to water from your benchmark, before any water is removed from the well (Fig. 5.6)
2. Remove the beeper tape from the well
3. Remove the desired volume of water from the well using the bailer (one liter for each group)
4. Record water level recovery slug test data form
   1. make first measurement ( ) as soon as possible after removing water from the borehole
   2. initially make frequent measurements, e.g. every 15 seconds
   3. when measurements at consecutive time steps differ by less than a few % double the time interval between measurements
   4. continue reading levels until about 2/3 (at least 63%) of the initial drawdown has been recovered, i.e. until , see slug test data form
   1. record slug test data on suggested form (Fig. 5.7)
   2. make a semi-log plot of the results as in Fig. 5.8 using either of the following approaches
      1. plot using spreadsheet program like Excel, set y axis to logarithmic
      2. add a 5th column giving the logarithm of head ratio (column 4 of form); plot on regular graph paper, using column 1 (time) for X, column 5 (log of head ratio) for Y