TASK DESCRIPTION
Laser-induced fluorescence (LIF) is an optical technique that exploits the detection of fluorescent compounds irradiated with laser light or filtered conventional light sources. The scope of this TTP includes a variety of techniques to exploit LIF in several environmental applications, including aerial remote sensing, handheld portable survey tools for surface uranium contamination, and hyperspectral portable technology for the detection of plant stress over intermediate distances (to be used at Walt Disney's EPCOT Center in a cooperative effort). This task has required the development of hardware, software, and analysis methods for ground-based and airborne laser-induced fluorescence imaging (LIFI) systems. LIFI applications include the detection of contaminants such as uranium (as uranyl oxides), and VOCs (polyaromatics, fuels, and vegetational stress as an indicator of surface and subsurface contamination).
This year's scope of work includes: (1) completion and fielding of the portable uranium survey tool at DOE sites for facility walls, floors, equipment, and surface soils, (2) integration of the airborne LIFI system into a helicopter geometry, and (3) a cooperative effort with scientists from EPCOT Center to determine the viability of using plant stress as contaminant and plant vitality indicators.
The uranium survey tool will be fielded at Oak Ridge Gaseous Diffusion Facility in cooperation with EM-40 personnel (ORGDF- Roy Sheely-POC). The survey tool will return to Santa Barbara, CA after an extended field exercise to be fitted with additional sensors before the second deployment.
The airborne LIFI system was configured last year for the DOE Convair 580T aircraft. The system will be reconfigured for helicopter usage. Deployment will now be possible in a variety of platforms including the U-60 class (Blackhawk, seahawk, pavehawk), Chinooks, and SH-3s. A technology transfer will most likely result in FY95 from hardware developed in the airborne project. A disk array interface card was developed in FY94 to facilitate high-speed, high-volume digital data transfer from the multi-tap digital camera to the 13 Gbyte storage array. The third task involves a series of cooperative efforts with EPCOT to investigate contaminant plant stress signatures and methods of detection. The Land Pavillion at EPCOT is a World Showcase for the R&D of technologies for agricultural application. This subtask included a Technology Exchange Symposium held at EPCOT on February 23-24, 1995. Scientists from universities, industry, DOE, and other agencies were invited to present some of their work and discuss the state of plant stress research. A summary will result that will outline the present areas of research and technology advances required to specify future remote sensing systems. In addition to working directly with EPCOT plant physiologists during FY95, a graduate student at Rochester Institute of Technology has been sponsored to investigate the radiometric specifications of LIF airborne measurements under real world conditions.
TECHNOLOGY NEEDS
Laser-induced fluorescence addresses the need for rapid survey tools for monitoring sites remotely, identifying contaminant "hot spots," and assisting in the cleanup activities and monitoring progress. Future efforts may include verification of site cleanup, if regulatory sensitivity can be achieved and verified through field tests. Development of an airborne survey tool for fluorescence and reflectance signature detection will continue. The system promises area coverage of sites that are spread out geographically, such as uranium firing sites, or sites that have poor access, such as clay cap areas. The system is being reconfigured for helicopter use. Conversion of the system, previously mounted in the Convair 580T to pallet mounted containers in the helicopter, will provide a rapid deployment feature to a variety of platforms.
The concept of plant stress detection is an active area of research at a number of federal agencies, as well as many universities. The EPCOT Symposia brought researchers together from many institutions in an effort to better understand and scope the applicability of LIF as a remote sensing tool.
ACCOMPLISHMENTS
During FY93 field tests at Oak Ridge Gaseous Diffusion Facility (K-25), it became clear that LIF images from uranyl compounds could be a great help to the D&D efforts at the site. FY94 activities focused on transforming the 1,000 lb laser pallet assembly (used in outdoor LIF field tests in FY93) into a portable laser survey tool that employed a handheld transmitter/receiver and provided real-time display. The uranium survey tool will be delivered to EM-40 personnel this year for evaluation as a D&D tool. EM-40 sponsored the packaging and initial deployment costs. The device will be used primarily as a rapid survey tool for D&D activities in the buildings where extensive salvaging of components has occurred over many years. This figure shows an artist's rendition of the uranium tool. The laser power supply, laser head, computer, and batteries are located in a 19 inch rack/crate. The laser is connected to the transmitter optics through a fiber optic. The camera signals are processed and redisplayed as false color composites at the view screen. Raw data is recorded on 8 mm tape. The detection algorithm developed last year requires that the fast shutter (MCPII) be controlled to collect delayed phosphorescence, as well as ambient illuminated frames from room illumination. These will be used as the background for visual reference. Frames from the luminescence of uranyl oxides are superimposed on the ambient illuminated frames to create a false color overlay of contamination over the gray- scale image of the room. The system has been successfully tested in the laboratory.
In FY94, the airborne system was successfully integrated into the DOE Convair 580T aircraft. After two weeks of flight tests, the Convair was removed from the DOE fleet due to budget considerations. The helicopter-based system will afford a smaller system that will be modular. Camera modifications, including a higher sensitivity CCD detector, will improve system sensitivity. As a result of the extensive component development in FY94, the digital interface from the camera to the disk array storage device is now a candidate for technology transfer to a disk manufacturer.
BENEFITS
Fluorescence techniques have the ability to detect signatures that are not observable by traditional remote sensing methods. The high spatial resolution of intensified CCD cameras and the time-resolved phosphorescence emission characteristic of the uranyl ion allow one to obtain a digital picture of the extent of surface contamination. This allows mitigation efforts to be focused on specific areas, which speeds the survey and lowers overall costs. The real-time image processing of the data into a false color composite on gray scale background allows the operator to quickly distinguish the uranium signature. Since the data is recorded on video tape, it can be reviewed for planning and review of D&D activities. The fusion of radiation data and position sensor information will greatly enhance the tool.
Participation with EPCOT Center in plant studies affords the opportunity to collaborate with world class plant physiologists to study the effects of plant pathogens and contamination. A variety of sensors will be used and compared to evaluate the concept of plant stress. EPCOT center will act as a focal point for collaboration across agency boundaries and act as a site for continued collaboration. The eventual development of robotics systems in other DOE/EPCOT collaborations will provide platforms for testing the concept of LIF on sites of agricultural interests.
The advantages of airborne systems for remote sensing are well documented. Fluorescence techniques have the ability to detect signatures that are not observable by traditional remote sensing methods. Airborne operations allow one to survey large areas in a cost-effective manner. Many DOE areas are located in remote areas, with practical access obtained only from the air. An aerial view allows identification of subtle changes and patterns that are not apparent from ground-based operations. High resolution imaging techniques under development allow one to obtain a picture of the extent and location of surface contamination. This allows mitigation efforts to be concentrated on specific local areas.
COLLABORATION / TECHNOLOGY TRANSFER
The laser-induced fluorescence project has often used the leverage of collaboration to control costs, especially in joint agency field exercises. Efforts with EPCOT scientists have involved scientists from the DOE Remote Sensing Lab, DOE Special Technologies Laboratory, Army Topographic Engineering Lab (Army Corps of Engineers), and Rochester Institute of Technology. FY93 field tests were performed in collaboration with the above-mentioned federal agencies, members of EM-50 and EM-40 at the Oak Ridge reservation, and EM-50 personnel at Savannah River. FY95 field tests at the Oak Ridge Gassious Diffusion Facility will be completed in collaboration with EM-40 at K-25 (Roy Sheely-POC).
FY95 technology transfer activities include the pursuit of an agreement with SYSTEMWARE, a disk manufacturer in Westlake Village, CA. A proposal was submitted through the Nevada field office for a joint effort to bring the disk interface card to the commercial market. SYSTEMWARE's market survey has confirmed that the activity is in the company's best interest.
FY 95 Contacts:
Dr. John DiBenedetto
Principal Investigator
Special Technologies Laboratory
5520 Ekwill Street, Suite B
Santa Barbara, CA 93111
(805) 681-2307
Dr. Leo Rogers
Technical Program Manager
Remote Sensing Laboratory - EG&G/EM
P.O. Box 1912, M/S RSL-19
Las Vegas, NV 89125
(702) 295-8726
Katie McWilliam
Technical Program Officer
DOE Field Contact
DOE/NVO
2765 South Highland
Las Vegas, NV 89109
(702) 295-1031
Dr. Caroline Purdy
Program Manager, CMST-CP
U.S. Department of Energy
Cloverleaf Building
19901 Germantown Road
Germantown, MD 20874-1290
(301) 903-7672
TTP Number: NV053002
None at this time.
