Objective:

There has been considerable progress made in the detection of buried unexploded ordnance (UXO) in the last 5 years. The Multi-sensor Towed Array Detection System (MTADS), supported by ESTCP, has demonstrated detection capability for all military ordnance to its maximum self-burial depth with location accuracies on the order of 15 centimeters. However, discrimination of UXO from ordnance fragments and other clutter remains as a problem. The U.S. Army Corps of Engineers Center in Huntsville reports that on a typical job, about 75 percent of the remediation costs result from digging non-ordnance targets. It has been shown that with careful mission planning and a modest on-site training effort, an MTADS survey/remediation project can do better than this. However, there is still substantial room for improvement in the discrimination ability, which will result in a direct reduction of remediation costs. This program will demonstrate a frequency-domain electromagnetic induction (EMI) sensor array intended to address this need.

Technology Description:

A vehicle-based towed array UXO detection and classification system is being demonstrated that integrates the proven efficiency, reliability, and locational accuracy of the MTADS with the demonstrated classification ability of the prototype frequency-domain geophysical electromagnetic (GEM) sensor developed by Geophex, Ltd. The project builds upon the existing MTADS field hardware, data acquisition, location, and baseline data analysis systems. It includes an upgrade to the data acquisition system, incorporation of new algorithms in the data analysis system, and acquisition and incorporation of an array of GEM sensors. Five to ten carefully chosen frequencies will be used to achieve the required discrimination. This will be the first efficient application of broadband electromagnetic sensor technology to large area surveys.

Expected Benefits:

The primary benefit of the proposed technology is economic. The Defense Science Board (DSB) set a goal for false alarm reduction of 10:1 in UXO surveys. In a controlled demonstration at Jefferson Proving Ground, the EMI spectroscopy approach utilized by Geophex, Ltd. achieved a combined percentage of correct ordnance and non-ordnance declarations of about 75 percent. This is a significant step toward the DSB goal in itself and, if achievable in a wide area survey in a less controlled environment, would reduce the cost of a typical clearance action by a factor of two. If the estimate of $15 billion for total UXO cleanup costs is realistic, the total savings over the next several decades will be enormous. (Anticipated Project Completion - 2005)

Principal Investigator:
Dr. Herb Nelson
Naval Research Laboratory
Chemistry Division, Code 6110
4555 Overlook Avenue SW
Washington, DC 20375-5342
Telephone: (202) 767-3686
Fax: (202) 404-8119
E-mail: herb.nelson@nrl.navy.mil