Many ranges and training areas on military installations are located near water environments such as ponds, lakes, rivers, estuaries and coastal oceans. When munitions leftover from previous military training and weapons testing activities migrate to coastal and inland waters, it can be difficult to retrieve them. Underwater environments pose a more unique set of challenges than dry land for established and emerging characterization technologies. Most of the areas that the U.S. Army Corps of Engineers and U.S. Navy have identified as potentially containing munitions are shallow water environments (0-120 feet), which pose a greater risk to human health.

SERDP and ESTCP have supported research to advance technologies that detect, classify and remediate underwater military munitions. In 2021, SERDP funded projects that will improve wide area and detailed surveys of munitions by quickly characterizing and mapping underwater environments, detecting munitions in cluttered backgrounds, classifying targets under complex conditions, and localizing potential targets to rapidly and accurately return for removal/disposal. The selected projects are described in greater detail below.

• Dr. Peter Menzel with Corvus Works UG and his team will quantify the influence of currents and waves on the mobilization and migration of objects, as well as analyze the burial and re-exposure of objects. This project will identify the critical conditions for mobilization, the probability of occurrence in areas of interest, and how far objects migrate. These efforts will reduce the need for repeated, expensive surveys by enabling continuous monitoring. (Project Overview)

• At the U.S. Naval Research Laboratory, Dr. Carter DuVal and his team aim to quantify munitions and explosives of concern (MEC) mobility and burial at dynamic riverine sites and identify and reduce the parameters necessary to predict mobility and burial in riverine environments for models. This project will improve Munitions Response Site management by decreasing the number of independent field observations and model parameters needed for running MEC mobility and burial predictive models. (Project Overview)

• To rapidly and accurately map targets, it is particularly important to characterize seabed soil. This requires a deeper understanding of how different soil behavior classes affect acoustic unexploded ordnance (UXO) detection and classification methods, as well as soil erodibility and mobility. This project with Dr. Nina Stark at Virginia Tech will identify effects of benthic biogenic processes on geotechnical soil properties and quantify the impacts of the different soil classes on acoustic UXO detection and classification methods. Her team will focus on developing a soil classification scheme the enables integration into the Underwater Munitions Expert System (UnMES), a UXO risk assessment scheme. (Project Overview) 

• Dr. Ahmad Abawi at HLS Research and his team will support UXO remediation systems by modeling the response of UXOs to sonar using the Coupled Finite Element/Boundary Element (CFEBE) model in a realistic ocean environment. Their efforts will help predict sonar performance, analyze measurements and design subsequent experiments. The project will mostly focus on application for the Multi-Sensor Towbody (MuST) system. (Project Overview)

• At Penn State’s Applied Research Laboratory, Dr. Daniel Brown and his team will develop a detailed survey that detects and localizes munitions in shallow water environments. The project will build upon the Sediment Volume Search Sonar (SVSS), a previous SERDP effort, to improve sonar hardware performance and signal processing of the sensor’s data. These efforts will advance target detectability in complex conditions by providing finer image resolution. (Project Overview)

• Sediment transport impacts munition mobility, burial and reemergence. The irregular nature of sediments in tropical coastal regions increases intergranular friction and hinders sediment mobilization. This project led by Dr. Sylvia Rodriguez-Abudo at the University of Puerto Rico, Mayaguez aims to quantify the effects of grain shape and angularity on munition mobility under the presence of oscillating fluid motion. Her team’s research will support the application of current efforts to predict mobility, burial and re-exposure of underwater munitions, like UnMES, in tropical settings. (Project Overview)

These projects will enhance current technologies and develop new approaches for wide area and detailed surveys of munitions in a variety of complex and shallow underwater environments. Such efforts will ultimately enable cost-effective characterization, remediation, and management of underwater munitions response sites.