Cascade - Ultra Violet Optical Screening Tool (UVOST)
Successful and cost effective LNAPL site management requires a CSM, including detailed knowledge of NAPL location and distribution. The Ultra-Violet Optical Screening Tool (UVOST) provides these data with unmatched speed, detail, and efficiency. Optimize your remedial design by finding, delineating and quantifying aromatic LNAPL with UVOST, a laser induced fluorescence direct sensing tool. UVOST is used to reliably delineate nearly any petroleum NAPL including gasoline, diesel, crude oil, kerosene, and many others. It can be deployed by any type of direct push platform.
The UVOST system uses a sapphire window to measure front-face fluorescence of the petroleum NAPL as the probe is advanced into the soil with nearly any direct push platform. Pulsed ultraviolet laser light travels down a fiber optic line and is reflected from a downhole mirror and out a sapphire window in the side of the probe. When this UV light impacts polynuclear aromatic hydrocarbons (PAH), it imparts energy to them. When the light source is shut off, the energy is given back by the PAH molecules in the form of fluorescence. This fluorescence travels through the sapphire window, into the probe and up to the surface via a fiber optic line. The waveforms and decay of the light is analyzed at the surface, the presence of PAH is noted and the type of petroleum can be determined. The signals are plotted versus depth as percent response of a reference emitter (%RE). Call out windows where detections occur show the waveforms, which are diagnostic of various products.