Hello,
Seems to be not so common, as there are no posts about it in other forums either.
This permit is only required in areas where one can assume the presence of archaeological monuments; for example, the Cologne area in the Rhineland.
Below is Art. 7 DSchG in full text:
Art. 7 Excavation of Archaeological Monuments
(1) Anyone who intends to dig for archaeological monuments or to carry out earthworks on a property for another purpose, although they know or suspect or must assume from the circumstances that archaeological monuments are present there, requires a permit. The permit can be refused insofar as this is necessary to protect an archaeological monument.
(2) The districts can declare certain properties by ordinance as excavation protection areas where archaeological monuments are to be presumed. In an excavation protection area, all work that may endanger archaeological monuments requires a permit. Art. 6 para. 2 sentence 2 and para. 3 apply accordingly. Excavation protection areas must be indicated in the land use plan.
(3) Paragraph 1 and paragraph 2 sentence 2 do not apply to excavations carried out or initiated by the State Office for Monument Preservation or with its participation.
(4) Anyone who wants to erect, alter or remove facilities near archaeological monuments that are wholly or partly visible above ground requires a permit if this can affect the existence or appearance of one of these monuments. Art. 6 para. 2 sentence 2 and para. 3 apply accordingly.
(5) If an excavation is to take place on someone else’s property, the owner can be obliged to allow the excavation if the State Office for Monument Preservation has determined that there is a particular public interest in the excavation. The holder of the excavation permit has to compensate the owner for any damage incurred.
Kind regards