Underwater unexploded ordnance discrimination based on intrinsic target polarizabilities – A case study

The Very Early Time Electromagnetic (VETEM) system, the High-Frequency Sounder (HFS), and the Tensor Magnetic Gradiometer System (TMGS) were developed by the U.S. Geological Survey (USGS) for applications other than unexploded ordnance (UXO). However, features of these systems may make them adaptable to UXO applications. VETEM is a time-domain electromagnetic (EM) induction system that utilizes full waveform recording. The HFS is a flexible frequency-domain EM system. The TMGS uses four sensitive 3-axis fluxgate magnetometers so that gradients of field components are recorded. Tests were conducted in air using a selection of inert UXO objects ranging from 20 mm to 105 mm in diameter. A nulled overlapped antenna arrangement was used for both VETEM and the HFS. It was found that this antenna configuration resulted in distinctly different responses to horizontal UXO objects aligned along the direction of traverse versus horizontal and perpendicular to the traverse. Vertical orientation of UXO objects resulted in smaller amplitude signals and an interesting slightly asymmetric “crater” shape response in plan view. The HFS response was a strong function of frequency, which is good for discrimination. The TMGS data are the most sensitive to ferromagnetic objects and the multi-component data hold the promise of accurate location, including depth, to UXO objects using a dipole mapping algorithm. Plans include increased sensitivity and multicomponent capability for the EM systems, advanced algorithms to enhance UXO discrimination for EM and TMGS systems and field evaluations at standard UXO test sites of the Strategic Environmental Research and Development Program (SERDP). Introduction UXO is one of the most pressing problems facing the Department of Defense and other government agencies that have lands that were once used for military training and are now closed or closing and being returned to civilian use. Cleanup of all UXO-contaminated lands using existing methods would be prohibitively expensive, so a great deal of effort is being directed to finding better ways to detect, locate and identify buried UXO. It is not sufficient to merely detect buried metal objects, because many of these objects are not UXO and pose no hazards. In many cases of range cleanup 70% or more of the cost consists of locating and removing harmless metal including soda cans, broken plow blades and fragments of ordnance that exploded as designed. Among the primary geophysical methods for detecting and classification are various time and frequency domain EM systems and magnetometer systems. Since the USGS developed some prototype EM and magnetic systems for applications other than UXO, and because some of these prototype systems have some unusual characteristics, we proposed to test, evaluate, and modify three of these systems, the VETEM system, the HFS, and the TMGS. We are now in the process of carrying out this work and this paper describes some of the results from laboratory tests.

There is universal agreement between the United Nations and governments from the richest to the poorest nations that humanity faces unprecedented global challenges relating to sustainable energy, clean water, low-emission transportation, coping with climate change and natural disasters, and reclaiming use of land. We have invited researchers from a range of eclectic research areas to provide a Roadmap of how superconducting technologies could address these major challenges confronting humanity.

The location and identification of unexploded ordnance (UXO) is a major challenge for environmental rehabilitation of former military firing ranges and bombing target areas. EM methods are in widespread use for the location of metal objects, however the presence of large quantities of scrap metal from successful detonation of munitions makes discrimination between munitions and scrap and munitions of various sizes a necessity in order for efficient location, digging and removal of UXOs to proceed. Several recent papers show that detailed three-component EM measurements followed by inversion to dipole moments of an EM target is effective in characterising a target, however such techniques require precise data, usually from stationary data acquisition. EM data acquired from a moving ground platform for UXO detection is typically high in motion-induced noise which limits the usefulness of decay-curve analysis in target characterization. We use a data set from the Australian Air Force Newholme UXO Test Range, Armidale, NSW, and show that a) images of time-window data are unsuccessful in discriminating between different types of munitions, b) adaptive decay index methods are ineffective due to high noise levels on the observed decay curves, and c) principal-component transforms of the data are successful in differentiating between different types of munitions. The method provides a tool for initial classification and prioritization of anomalies from a surveyed area, thus facilitating preparation of an efficient program of follow-up surveys and site clean-up.

Summary This paper explores the integration of 3D Electrical Resistivity Tomography (ERT) and 3D Induced Polarization (IP) for detecting unexploded ordnance (UXO) in subsurface environments. The methodology leverages the conductive and chargeable properties of metallic UXO materials, providing a powerful alternative to conventional geophysical techniques such as Ground Penetrating Radar (GPR), Electromagnetics (EM), and magnetometry, especially in urban or noise-contaminated settings. Using high-resolution, multi-channel acquisition systems and advanced inversion software, detailed resistivity and chargeability models are constructed to highlight subsurface anomalies. A critical indicator is the dipolar signature-spatially correlated resistivity and chargeability anomalies-that characterizes metallic targets. Field case studies in Trento and Naples validate the method’s effectiveness, confirming its ability to identify small-scale UXO targets in challenging site conditions. Compared to 2D methods, the 3D approach enhances detection accuracy, eliminates interpolation errors, and captures complex geometrical features. The results support ERT3D-IP as a non-invasive, cost-effective, and adaptable solution for UXO detection, with broader implications for geophysical applications in civil and defense projects.

9 - The contribution of geophysics to landmine and unexploded ordnance (UXO) detection: Case study in the Egyptian environment

Summary During an unexploded ordnance (UXO) clean-up project, most of the items excavated are not UXO, but are harmless scrap metal. If these items can be determined to be non-hazardous without digging, the cost of a site clean-up can be cut by a substantial amount. Reliable classification of suspected UXO targets using geophysical survey data is now possible. This paper provides a summary of new advanced electromagnetic sensors and related software technologies to consistently classify suspected UXO and buried munitions vs. non-hazardous buried metallic objects. The technology and the tools have matured to the point where classification can be (and are) routinely applied to UXO clean-up projects in a transparent and reproducible approach. This methodology is now being accepted and required by US government program managers and regulators in clean-up projects that span a range of site conditions.

This paper describes the risks posed by the presence of unexploded ordnance (UXO) during the construction, operation & maintenance (O&M) and decommissioning/demolition of coastal and maritime projects. It summarises an industry ‘good practice’ guidance document which has recently been published by the Construction Industry Research and Information Association (CIRIA). The paper focuses on assessing and managing UXO risks in the marine environment through the application of a robust risk management framework. This enables application of a combination of risk avoidance and/or risk mitigation approaches that will not only reduce risks, but also safeguard the health, safety and wellbeing of personnel and help protect the natural environment. The paper refers to latest international standards and research on this topic and draws lessons from case studies.

On-line electrochemical monitoring of (TNT) 2,4,6-trinitrotoluene in natural waters

A review of processes involved in the exchange of persistent organic pollutants across the air–sea interface

During the 20st century, millions of tons of munition were dumped into the oceans worldwide. After decades of decay, the problems these unexploded ordnance (UXO) are causing are starting to become apparent. In order to facilitate more efficient salvage efforts through e.g. autonomous underwater vehicles, access to representative data is paramount. However, so far such data is not publicly available. In this paper we present a dataset of multimodal synchronized data for acoustic and optical sensing of UXO underwater. Using an ARIS 3000 imaging sonar, a GoPro Hero 8 and a custom design gantry crane, we recorded close to 100 trajectories and over 74,000 frames of 3 distinct types of UXO in a controlled environment. Included in this dataset are raw and polar transformed sonar frames, annotated camera frames, sonar and target poses, textured 3D models, calibration matrices, and more. The dataset is publicly available at https://zenodo.org/records/11068046. The code for processing the raw data is available at https://github.com/dfki-ric/uxo-dataset2024.

Data were gathered at the Yuma Proving Ground (YPG) to demonstrate the effectiveness of the Tensor Magnetic Gradiometer System (TMGS) for the detection of buried unexploded ordnance (UXO). After a rigorous reduction of the TMGS data, the magnetic gradient tensor was calculated. From the gradient tensor values, the tensor invariants were determined. By comparison of known target locations and Very Early Time Electromagnetic (VETEM) data to the mapped invariants, it was found that the invariants do an excellent job delineating UXO targets and that their correctly positioned unipolar characteristic make them easier to compare to electromagnetic (EM) results than total field magnetic measurements.

Geophysical prospection as a noninvasive archaeological survey technique has become a widely applied discipline that is currently finding its way into the former World War 1 (WW1) battlefields. Because of the imminent danger of unexploded ordnances, noninvasiveness is the key to exploring the subsurface containing our buried heritage. Fluxgate magnetometry (FGM), a frequently applied prospection technique in archaeology and unexploded ordnance detection, is not always satisfactory in this area. This is due to the high density of ferrous objects masking the underlying features of interest. Frequency domain electromagnetic induction (EMI) has proved to be less sensitive to metal objects, thereby revealing more WW1 traces. Another advantage of EMI is that soil disturbances related to shelling and metal objects can be classified with higher precision by combining magnetic and electrical conductivity data layers. After evaluating both prospecting techniques on maximum feature coverage, feature type identification, metal object filtering, and localization, EMI was shown to be the most successful. Although FGM is not inferior (providing high survey speed and density with multisensor arrays and reliability in pinpointing features, etc.) overall, EMI is the preferred option on sites with heavily disturbed soil. In this paper, these findings will be demonstrated with survey examples, case studies, and numerical analyses from the WWI battlefields of Flanders.

Ultra wideband (UWB) radar has been extensively investigated both theoretically and practically for the identification buried artifacts. Ground probe radar (GPR) concentrates on the identification of lightly buried land mines, unexploded ordnance (UXO) and archeological targets. The same technology is proposed in a similar context for the rapid identification of in vivo implanted metallic prostheses. The technique is based on resonance based target identification and the paper investigates UWB scattering from a metallic hip prosthesis in free space as a first step in the identification process.

The process of land acquisition frequently presents large difficulties for socially as well as economically marginalized communities since secured systemic inequalities also power imbalances often disadvantage them. Often these groups do not have needed resources or legal skill to use hard legal systems. Therefore, they become vulnerable toward inadequate compensation and even forced displacement. Arbitration, as being an alternative dispute resolution (ADR) mechanism, offers up a more accessible, efficient, and equitable means for resolution of disputes by providing a potentially transformative path for getting to justice for these diverse communities[1]. The paper explores the role of arbitration in land acquisition cases, with emphasis on its impact on the environment as well as on marginalized communities. At first, the paper goes over the core principles for land acquisition and also covers all of the legal frameworks that govern that process, all rights for affected communities, the mechanisms that are designed for ensuring fair compensation, and whether anything has degraded the environment. It then examines specific challenges faced by marginalized groups amid land acquisition disputes and this examination spotlights socio-economic barriers that impede their ability to assert their rights and secure just outcomes. Arbitration's role as being a tool that helps with improving access to justice is a key focus in the discussion. People laud arbitration since it is flexible and confidential. It also lets people resolve issues faster than do customary courts. Time, cost, also complexity might deter marginalized communities when they litigate. These attributes can make it be an attractive option for them in other cases. This legal study evaluates how arbitration offers procedural advantages for parties, such as parties selecting arbitrators who have expertise in land acquisition in addition to parties tailoring procedures that are sensitive to the needs of vulnerable parties. Yet the paper considers arbitration's limitations and challenges critically too. Drawbacks still exist while arbiters can process cases more accessibly and with streamlining. Parties can remain imbalanced in power, especially when a state or powerful corporation has power over a marginalized community with limited resources. The paper explores the potential for arbitration to perpetuate these imbalances in the event that arbitration is not adequately regulated, stressing the necessity of ensuring that arbitration processes are transparent, fair, and also inclusive. It also considers what is the major role that is of legal representation and advocacy. This role is vital to leveling the playing field for marginalized communities during arbitration proceedings. This study also explores one case study from one jurisdiction employing arbitration for land acquisition disputes of marginalized groups. These case studies offer valuable perceptions into the effectiveness of arbitration in delivering justice as well as the conditions under which it can either succeed or fail. These case studies also provide lessons on best practices for designing arbitration processes so the processes respond to the needs of socially as well as economically disadvantaged parties.

While it is recognized that protected areas are important for biodiversity conservation and human wellbeing, governments struggle to establish and/or enlarge protected areas. Land acquisition and the challenges encountered by governing institutions in funding protected area systems expansion is discussed in this paper using the Capital Regional District (CRD) Land Acquisition Fund as a case study. We briefly discuss land acquisition in British Columbia and in the CRD, and offer an overview of the CRD Land Acquisition Fund and the public participation process that led to its establishment. We emphasize the importance of developing political and citizen support, and a shared vision about expanding protected areas systems - a key element for nearly doubling the parkland base of CRD Regional Parks in less than 20 years. We conclude by offering the lessons learned through the case study and provide guidance for policy and governance directions with regard to land acquisition.