Formal:
* Archaeological dig
* Dig site
* Excavation
* Dig
* Site
* Exhumation site (if it's specifically about digging up human remains)
* Quarry (if it's for extracting stone or other materials)
Informal:
* Dig
* Hole in the ground
* Work site
* Construction site
* Digging spot
The best choice will depend on the specific context and the desired level of formality.