1,083. Graves on Chol HaMoed

Shvisas Yom Tov 8:8

A grave may not be dug on chol hamoed, nor a mausoleum constructed, in order to have them ready in case someone dies. If a grave was already dug, it may be adjusted on chol hamoed, such as increasing or decreasing its size to be ready for its intended occupant.

Shvisas Yom Tov 8:9

A corpse and bones may not be moved from one grave to another on chol hamoed, neither to a location of less honor nor to one of more honor. This is not even permitted on a regular weekday, except to move the deceased to a family plot. In such a case on regular weekdays, one may even move the deceased to a location of less honor.