Test Results From Two Prototype Electromagnetic Systems At The Serdp Standardized Uxo Test Site At Yuma Proving Ground, Arizona

During February and March, 2003, the U. S. Geological Survey (USGS) conducted tests of the<br>time-domain Very Early Time Electromagnetic (VETEM) system and the frequency-domain High<br>Frequency Sounder (HFS) at the Strategic Environmental Research and Development Program (SERDP)<br>Unexploded Ordnance (UXO) Standardized Test Site at the Yuma Proving Ground (YPG), Arizona. An<br>objective of these tests was to assess the potential of these systems for UXO applications and to help us<br>formulate design parameters for an improved electromagnetic system designed specifically for UXO.<br>Although neither VETEM nor the HFS was designed with UXO applications in mind, both detected the<br>majority of the buried targets in the Calibration Area at YPG. VETEM responded to earth conductivity<br>as well as to the buried UXO objects as did the HFS above 20 kHz. Earth response was anticipated<br>because both VETEM and the HFS were designed to image earth conductivity. Spatial filtering reduced<br>earth response and system artifacts and enhanced target responses.<br>We have concluded that a modified “on-time” time-domain system with a multi-component<br>antenna array and the ability to measure to later times than VETEM provides could improve the<br>detection performance we obtained from VETEM and the HFS at YPG. In addition, such a system<br>would furnish the diverse temporal, spatial, and vector component data that should optimize the<br>potential for UXO target discrimination and identification.