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GAMMA-METRICS and Oak Ridge National Laboratory (ORNL) have developed a prototype portable Toxic Chemical Analyzer (TCA) for environmental screening using surface enhanced aman scattering (SERS) technology. The focus is on detection of anthropogenic chemicals such as polycyclic aromatic compounds. In this instrument a laser illuminates a small sample of analyte on a substrate of silver coated particles. Light scattered from the illuminated spot is analyzed to determine the chemicals in the analyte.The development process involved miniaturizing the instrument from a large laboratory table-top device to a small portable package, then ruggedizing the components and the packaging to withstand field conditions. A reference design for a commercial instrument has been developed. The instrument employs internal direct optics or, optionally, an external, in-situ probe connected by fiber optics to internal components. A substrate dispenser is used to refresh the substrate in preparation for a new measurement. Measurement results to date show that high quality spectra can be obtained with the portable system. 180/SP1E

We produced a product design concept for an economical, automatic, shipping container inspection system to be used for detection of contraband, including illicit drugs, and for trade enforcement via shipping manifest confirmation. Using nondestructive, three dimensional imaging, nuclear techniques the system can see deeply into the cargo by generating a spatial image of an entire container's contents automatically and in real time. Its cost is lower than present inspection methods. The approach divides a container into numerous, small, volume elements that are individually interrogated using pulsed fast neutron analysis. Acquired information is subjected to analysis based on a neutron-gamma physics data base and is enhanced using imaging .and discrimination techniques. We have designed, built, and operated a laboratory apparatus which has demonstrated the attractiveness of this approach. Experimental data were found to agree with design expectations derived from computer modeling. By combining selected element signatures and phenomenological measures, together with discrimination algorithms, we demonstrated that a full-scale inspection system needs only 10 -15 minutes to process an 8 foot x 8 foot x 40 foot container in order to detect hidden contraband. PROJECT SCOPE AND METHOD PRESENTATIONGAMMA-METRICS is performing an R&D effort supported by the Advanced Research Projects Agency to test a practical method of detecting contraband in cargo containers and to demonstrate a cargo inspection system.1'2 The objective is to build on the R&D results by producing and testing a practical, full-scale unit. Designed mainly for port-of-entry use, its applications range from shipping manifest confirmation for tariff collection to illegal substance detection for criminal activity interdiction.The inspection system design requirements appear in Table 1. The system needs to be large enough to perform detailed checks of cargos in full..sized trucks and containers but not require that they be opened. It must generate accurate results and assessments quickly, automatically, safely, and in real time and yet perform at a lower cost than present manual methods. To reduce risk it should be mechanically straightforward and based on proven technology.The fast-neutron based system directs beams of neutrons into a suspect container, detects and identifies its contents by the resulting gamma ray emissions. The neutrons and gammas have high energies and thus penetrate deeply into cargos. Gamma energy spectra form a three dimensional (3-D) spatial image that characterizes the cargo materials as a function of position. The system 488 ISP/F Vol. 2093 0-8194-1366-61941$6.00 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 07/22/2015 Terms of Use: http://spiedl.org/terms can then automatically flag either illicit substances or cargos that fail to match the manifest.This approach is sensitive to elemental composition and, in contrast to x-ray based methods, can distinguish between light elements and elements that are close to each o...