Can I use my septic or cistern tank above ground? Posted on April 21, 2016 by Mark Peabody No. Our below-ground tanks are only designed for direct burial applications. We do have a wide range of above ground tanks available for above-ground applications, including holding tanks designed to slide under mobile office trailers. Mark Peabody How deep can I bury my septic or cistern tank? Do I have to use sand or pea gravel for bedding when installing my septic or cistern tank?