For further information click title. The LIF approach is based on identification of compounds that fluoresce, principally the heavier petroleum compounds. The tool works well for free product in the vadose zone. It does not see dissolved phase constituents because there is not enough material presented to the window of the probe. The signal is usually elevated in smear zones but the tool cannot resolve what is in the water vs what is on the soil.
Chlorinated compounds don t fluoresce well.
However if they have a high petroleum content dissolved in them, then by association you may be able to predict their presence. For further information click title. It is normally fairly easy to locate zones of clays and silts from sands. The vertical profile can be used to select optimum locations for collecting water, soil gas and soil samples. For further information click title.