Continued from May 5, 2016.
The position of all artifacts must be carefully recorded, and, once recovered, the artifacts should be stored in water until they reach the preservation laboratory. A variety of methods are employed to stabilize artifacts recovered from an underwater environment, depending on the composition of the material and whether it came from fresh or slat water.
Waterlogged organic materials, such as wood, are normally preserved by replacing the water with a bulking agent such as polyethyne glycol (PEG) or sugar. Ferrous metals are ordinarily stabilized through electrolytic reduction. For large objects, like cannons, the process can take several years to complete.