You searched for: “rescue archeology
rescue archaeology, rescue archeology (s) (noun) (no pl)
The branch of archaeology devoted to studying artifacts and features on sites which are imminently threatened by development in the form of the construction of dams, buildings, highways, etc,: Rescue archaeology is concerned with the threats to archaeological remains occurring in the form of road-building, road improvement, new building of houses, offices, and industrial complexes, the flooding of valleys for reservoirs, and improved farming techniques involving the use of deep plowing.

The rescue, or salvage, archaeologist, is concerned with the retrieval of as much information as possible about the archaeological sites before they are damaged or destroyed. Frequently time is too short and funds are too limited for anything but a brief survey.