Unexploded Ordnance (UXO) and Discarded Military Munitions are found in many coastal regions. They are potentially present in U.S. coastal waters that coincide with former test firing ranges or underwater dump sites and can cause a potential risk to personnel as the ammunition or explosive was not detonated. These objects are continuously exposed to environmental influences such as saltwater, which causes corrosion, and waves and currents as well as mobile seabed sediments. Thus, the management and risk assessment of the potentially numerous and diverse object types is a big challenge. For site managers, the location of the objects, along with their type and condition, are of particular interest. Even if these pieces of information were known from surveys, the horizontal and vertical (with respect to the seafloor) locations of particular objects may vary due to continuous environmental influences. Thus, at the least where objects of interest are known to remain on or in the seabed, a scheduled program of monitoring may be recommended.

This project aimed to quantify the influence of currents and waves on the mobilization and migration of objects of interest, including the role played by migrating bedforms. This quantification also included analysis of the (self-)burial and re-exposure of objects. Ultimately, the critical conditions for mobilization need to be identified, along with a probability of occurrence within the area of interest (AoI) and analysis of how far objects subsequently migrate. This allows for informed decisions to be made regarding ongoing monitoring, significantly reducing the frequency of repeated and expensive surveys for those locations where the risk of object migration is demonstrated to be low under the prevailing environmental conditions.

The AoI for this project was the Formerly Used Defense Site at Fort Pierce Naval Amphibious Training Base, Florida. The environmental and technical information were collected, imported, and analyzed. The existing mobilization model was applied on the AoI and objects of interest and the weaknesses and strengths of the existing model were found. It was shown that the mobilization model UXOmob can be combined with the burial model of Whitehouse. The burial model of Whitehouse was updated to create DRAMBUIE 3.0 which formed the basis of the burial model used in the UXOmob simulations in the AoI.

As Dr. Helen Morrison left the project, the Lattice Boltzmann Simulations were not continued. Instead of these, TELEMAC was successfully implemented and used to model the currents, tides, waves and the morphodynamics in the AoI. First test simulations were validated successfully.

The UXOmob software was completely re-designed and set up in C++ to increase the performance and allow for spatial analysis of long and areally extensive time series. An algorithm that considers a local vertical change of the seabed due to morphodynamics including erosion and accumulation of sediment was included and tested. Thus, the second Go/No-Go-Decision point was passed successfully.

From available burial data, a sensitivity study was completed to quantify the importance of the variables, influencing the burial process of UXO. The most important variables were used to set up a neural network which, after training, was implemented within the framework of the existing DRAMBUIE 3.0 model. This research version model is referred to as DRAMBUIE ANN.

For a systematic cross comparison of the existing burial and mobilization models, a classification procedure was developed and described. For this purpose, the relevant literature was reviewed and first examples of the classification were shown.