In some parts of the world, there is growing concern over the threat posed by elderly wrecks. In many cases these wrecks are in coastal waters and port approaches and have received only superficial attention in the past. Often the priority was to remove the upperworks and so deal with the obvious hazard to navigation. In some instances this has left in place a potential long-term pollution problem. Today, there is a growing appreciation of the risk of persistent leakage from wrecks which continue to deteriorate as the years go by.
Many elderly vessels are now partially or totally buried in mud and sand. A high proportion of the wrecks are in poor condition; special techniques are required to clear away the deposited material, in order to expose the structure and allow expert inspection prior to an attempt to recover pollutants and/or clear the wreck.
There are many thousands of wrecks of this type along the North American seaboards, in West European waters and in heavily trafficked areas elsewhere in the world. Many of these ships were lost as a result of military action during two world wars. There is a growing demand for salvage assistance to deal with long-term pollution problems.