Technologies under development for the detection and discrimination of munitions and explosives of concern (MEC), which include unexploded ordnance (UXO) and discarded military munitions (DMM), require testing so that the performance can be characterized. To that end, Standardized Test Sites have been developed at Aberdeen Proving Ground (APG), Maryland, and Yuma Proving Ground (YPG), Arizona. The test sites provide a diversity of geology, climate, terrain, and weather as well as diversity in ordnance and clutter. Testing at the sites has been independently administered and analyzed by the government for the purposes of characterizing technologies, tracking performance with system development, comparing performance of different systems, and comparing performance in different environments. By hosting the demonstration of detection systems since 2001 and publishing performance results in a standard format on the internet, the program has served as a tool to quickly assess the abilities of off-the-shelf (OTS), developmental, and state-of-the-art (SOTA) technologies. The following is a summary of where UXO detection technology stands based on the results from the program through May, 2006.
Three basic sensor types were tested at the sites, which include electromagnetic induction (EMI or EM), magnetometer (MAG), and radar varieties. These sensors were sometimes combined so that two types would be a part of one system. Such a system is referred to as a dual system. The sensors were typically mounted on one of five platform types for carriage. These types were towed, pushcart, hand held, sling, and litter (referred to as 2-man) varieties. The latter three types were considered man-portable types.
The basic types of test areas used included open field (flat open), mogul (small mounds), wooded, and extreme desert types of terrains with YPG providing a sand soil and APG a silty loam soil. A test grid, referred to as a blind grid, where potential item positions are known, was also part of the test areas. All test areas typically contained 14 standard ordnance types ranging from small submunitions to 155-mm projectiles. Many types of ferrous-based clutter items typically ranging in mass from approximately 0.005 to 25 kg were inter-dispersed in the test areas with the ordnance items.
The SOTA UXO detection systems are challenged by targets close to other ordnance or clutter, by targets at depths approaching 11 diameters (D) and beyond, and by the smallest of munitions (20-mm projectiles). Such target distributions are site-specific; thus, the level of their occurrence in real-world cleanup sites will dictate development emphasis. When these types of targets do not exist at a survey or test site, and good quality controls (QCs) are in place for navigation, detection rates of 0.90 to 0.95 would be expected by the best detection technologies in a UXO field of “diverse” composition. In the same type of UXO field with only large types (> approximately 105-mm) of ordnance, probability of detection would be at or near 1.0. Detection rates may drop by as much as 30 to 40 percent in severe terrains.
The percentage of Ground Truth (GT) detected at a site similar to the test sites can be increased by employing additional systems to survey the site. Results from the test sites indicate that the benefits of this practice diminish past the addition of one or two systems depending on the spacing or density of the GT.
Geophysical mapping technology has consistently outperformed Schonstedt systems in all but the most severe of terrains. Results have demonstrated that this technology should be used when at all possible and practical.
Minimal discrimination ability of SOTA UXO detection systems is seen at the standardized sites. Based on cost payoffs of any discrimination ability, justification for investments in the sites to promote the development of this ability appears warranted.
Performance measures of detection and discrimination ability for UXO detection systems representing the SOTA were evaluated, and the results presented were based on testing performed at the standardized UXO testing sites. The standard GT composition and test metrics at the sites allowed comparative analysis of various system technologies. Insight was gained into identifying parameters affecting system performance. Possible QC issues were identified. Optimal configurations were identified. Furthermore, improvements to the test sites have been suggested on the basis of the test result findings. In summary, SOTA UXO detection technology, as demonstrated at the standardized UXO testing sites, has been characterized and evaluated on a broad but general level. Therefore, the objectives of the standardized UXO test sites have been met.
This ESTCP-funded program has ensured that critical UXO technology performance parameters such as detection capability, false alarm rates, discrimination, reacquisition, and system efficiency are determined through standardized test methodologies, procedures, and facilities. The Standardized UXO Technology Demonstration Site Program involves collaboration of several organizations and has built on the experience and expertise of each of the participants to establish realistic and cost effective standardized demonstration sites.