Upvote:4
As far as universal rules are concerned, Canon 1243 is relevant:
- Appropriate norms are to be enacted by particular law for the management of cemeteries, especially in what concerns the protection and fostering of their sacred character.
The depth of a grave is part of the cemetery's management, and is governed by βparticular lawβ β which might be a civil law or a ruling in a particular territory (Conference or even diocese).
My translation is prepared by the Canon Law Society of Great Britain and Ireland, 1983