&EPA
                                  United States
                                  Environmental Protection
                                  Agency
                EPA/540/MR-95/519
                August 1995
                                 SUPERFUND  INNOVATIVE
                                 TECHNOLOGY EVALUATION
                                  Demonstration Bulletin

                              Rapid Optical Screen Tool (POST™)

                                            Loral Corporation
Technological Description: The Loral  Rapid Optical Screen
Tool (HOST) is a tunable dye laser system used for the detection
of petroleum, semi-volatile, and some volatile organic compounds
in  soils. The technology is used in conjunction with a cone
penetrometer (CP).

The HOST components consist of a modified cone penetrometer,
monochromatic lasar, tunable dye laser,  detection system, and
control  computer.  A complete system consists of a Co  truck,
hydraulic rams, associated controllers, and the HOST itself (Fig-
ure 1).  The weight of the truck provides  a static reaction  force,
typically 20 tons, to advance the CP. The CP, which is mounted
on the  end of the series of push rods,  contains sensors that
continuously log tip  stress and sleeve friction. The  data from
these sensors is used to map subsurface stratigraphy. Conduc-
tivity  or pore pressure sensors can be driven into the ground
simultaneously.

The ROST can be deployed with any conventional CP system
and advanced along with other types of  sensors. The modified
CP contains a sapphire window that is mounted flush with the
outside of the stainless steel push rod. The sapphire window is
mounted above the cone penetrometer tip. Light from an excita-
tion laser passes  through the sapphire window and  is directed
onto  the soil through which the cone penetrometer  is pushed.
Certain contaminants ir the soil fluoresce  when exposed to
different  wavelengths of light. Fiber optics return this fluores-
cence information to the surface.

The main ROST system Icomponents are:

 •  Neodymium-doped Yttrium Aluminum Garnet  (Nd:YAG) pri-
   mary laser (Monochromatic laser)
 •  Tunable dye laser pumped by the Nd:YAG laser
 •  Fiber optic cable    j
 •  Monochromatorto resolve the return fluorescence as afunction
   of wavelength
 •  Photomultiplier tube (PMT) to convert photons into electrical
   signals           ]
 •  Digital storage oscilloscope to capture waveforms from the PMT
 •  Control/analysis computer and software

The ROST system can be operated in both dynamic (push) and
static  modes.  In the dynamic mode, the cone penetrometer
equipped with the LIF sensor (modified cone penetrometer) is
advanced into the soil. In this mode, the sensor measures fluo-
rescence versus depth, the excitation laser wavelength and fluo-
rescence emission monitoring wavelength are held constant. The
fluorescence emission intensity is plotted as a function of  depth
below ground surface. The excitation and monitoring wavelengths
 Figurel. Truck mounted cone penetrometer with ROST.'
                                                                                         Printed on Recycled Paper

-------
are selected based on the target compounds of interest. These
settings can be set at a wavelength determined during the labora-
tory or field analysis.

Once areas of significant contamination have been identified in
the dynamic mode,  the HOST  system can be operated  in the
static mode to identify fuel types. In this mode, the sensor is held
at a fixed depth. At this time a wavelength-time matrix (WTM) is
obtained. The WTM  can be used to  fingerprint a waste. Loral is
developing a WTM library for this application. The fluorescence
technician, who is observing the fluorescence signal during the
dynamic mode, can  simply signal the hydraulic operator to  halt
the push and collect WTM. The ROST system also can operate in
the static mode when additional  push  rods are  added to the
string.

Threa people are needed to operate the Loral ROST. Currently,
the technology  is marketed as a service, and is not for sale.

Waste Applicability: The Loral ROST was designed to qualita-
tively  identify classes and relative amounts of petroleum, PAH,
and volatile organic compound contamination in subsurface soil
samples.

Demonstration Results: The technology demonstration occurred
in EPA Region 7,  at sites in Iowa, Kansas, and Nebraska. The
sampling and field analysis was conducted during September
1994.

An Innovative Technology Evaluation Report (ITER) describing
the complete demonstration will be available  in late 1995.

Acknowledgment: This Bulletin was prepared by the U.S. Envi-
ronmental Protection Agency, Office of Research and Develop-
ment, National Risk Management Research Laboratory, Cincinnati,
OH 45268.

For Further Information:

EPA Project Manager:

J. Lary Jack
U.S.  EPA
Environmental Monitoring Systems Laboratory
P.O.  Box 93478
944 East Harmon
Las Vegas, NV 89193-3478
702-798-2373^         ...._.--.....-.          -_    ._.,._._
Fax:702-798-3146
United States
Environmental Protection Agency
National Risk Management Research Laboratory (G-72)
Cincinnati, OH 45268

Official Business
Penalty for Private Use
$300
                                     BULK RATE
                                POSTAGE & FEES PAID
                                         EPA
                                   PERMIT No. G-35
EPA/S40/MR-95/519

-------