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To obtain an accurate
sample using a bailer,
just follow these basic
instructions:
1) Gently lower the
bailer down the
groundwater well column.
Do not let the bailer
crash into the water
table. This will cause
agitation and turbidity
through surging and the
sudden impact of the
sampling device.
2) As the bailer
approaches the water
level within the well,
be sure to ease the
bailer into the water
table for the first 3-6
inches of the bailer
length. The recommended
rate of descent for this
step is five to 10
seconds.
3) Once the bailer has
been gently lowered into
the water table, allow
the bailer to descend on
its own until it fills.
Do not allow the bailer
to descend to the very
bottom of the well. If
the bailer comes in
contact with the bottom,
it could disturb the
sediment that may be
settled at the bottom of
the well. This will also
cause turbidity within
the well and your
sample.
4) Once the bailer
fills, retrieve the
bailer from the well
slowly, in a steady,
smooth motion. It is
neither necessary nor
recommended to jerk or
jig the bailer line.
By simply following
these basic steps, you
will retrieve accurate
groundwater samples in a
cost-effective and
timely manner. This
extra care during
groundwater sampling
when using a bailer adds
only one to two minutes
of additional time to
complete the task. By
utilizing these methods,
sampling with bailers
will significantly
reduce agitation and
turbidity and provide
you with a simple,
accurate and
cost-effective means for
obtaining groundwater
samples. |