|BAT Groundwater sampler |
The BAT Groundwater Sampler - Envirosampler® - is ideal for quick, discrete sampling of both liquid and gas phases at specific depths. All elements of the BAT System, including the encapsulated samples, are hermetically sealed, preventing loss of volatile components. The BAT Envirosampler® integrates field operations with laboratory techniques.
The BAT Envirosampler® contains three basic components:
- BAT MkIII Filter Tip, installed at the sampling depth
and attached to an extension pipe
- An evacuated sample collection tube
- A double-ended injection needle
Both the filter tip and the sample tube are sealed with a flexible septum.
Typical applications for the BAT Envirosampler® are:
- screening of contaminated sites
- long-term monitoring of groundwater and soil gas
The sample tube is inserted into a sampler housing which also is equipped with a holder for the double-ended needle. The sampler is lowered down the extension pipe onto the the BAT Filter Tip and simply by gravity the double-ended needle penetrates both the septum in the filter tip and the septum of the sample tube. A temporary, leak-proof connection is thus established between the sample tube and BAT Filter Tip.
Due to the action of both the groundwater pressure and the suction in the sample tube, groundwater and/or soil gas will be drawn into the sample tube. Upon lifting the BAT Envirosampler® the flexible septa in both the filter tip and the sample tube will automatically reseal. The liquid and/or gas sample is thereby kept hermetically sealed all the way from the point of sampling into the laboratory.
The flexible septum in the BAT MkIII Filter Tip can be pierced hundreds of times without loss of its automatic, self-sealing function. This makes possible long-term monitoring of installed BAT Filter tips with a maintained precision and accuracy.
Experience & references
The US-EPA and other high conformance requirement groups have adopted the BAT technology as appropriate and preferred for many environmental characterization applications. The repeatability of the data is cited as one key reason for this reference. BAT technology has also been scrutinized by many other investigators, and has met with widespread acceptance.