In Paul Turner's Blog by Paul Turner

Q:  Can you provide directions in regards to the actual plumbing of a sacrarium?  How does it drain directly into the ground?  What short of pit is necessary – does the pit have a particular type of gravel/sand etc.
A:  This is beyond my expertise. The liturgical documents do not describe anything about a sacrarium, other than its existence. Some municipalities have plumbing legislation over such matters. I wish I could help more.