32
ERDC/CRREL TR-02-12
The mean concentration of TCE in the PDB samplers was significantly lower
than in the controls after 23 days' contact. Although this difference is not large
(14%), it may reflect a temporal shift in the water quality as a result of sporadic
treatment at the site. However, it may also be that in spite of our best efforts,
slow-flow sampling obtained a slightly different water sample. As mentioned
previously, the mean concentrations for all five devices were lower than the
equivalent mean for the control samples taken using slow-flow sampling.
One final note: both the PneumoBailer and the Discrete Interval Sampler
did occasionally yield what appeared to be anomalous results. We are not certain
whetherthis indicates some type of malfunction and is reason for concern or not.
Leaving these devices in the well and allowing the well to recover prior to
sampling could reduce the impact they have on the wells. The one exception to
this would be the Kabis Sampler, which fills almost immediately after it stops in
the well.
Previous Page
