ABSTRACT
A new laser-induced fluorescence (LIF) probe identifies and semiquantifies classes of hydrocarbon compounds in contaminated subsurface soils. The probe is advanced into the subsurface using cone penetrometer testing (CPT) equipment and identifies hydrocarbon classes by use of a multichannel excitation–emission matrix (EEM). The LIF-EEM instrumentation is capable of assessing common subsurface hydrocarbon contaminants at depths up to 50 feet. The LIF-EEM techniques show considerable merit, particularly the combination of hydrocarbon classification and semiquantification. The LIF-EEM probe on CPT equipment could provide an economical, rapid assessment of contaminated sites. Data resolution on a cm scale coupled with the significant volume of subsurface information generated by this technique provide an excellent database to use with commercially available software for visualizing the three-dimensional extent of contaminants. Use of the probe is dependent on its ability to penetrate subsurface soils to the desired investigation depth.
