Deep trenches to fill before Travertine deck installed
I'm building a pool. They dug deep trenches around the pool for the piping. I plan on having a travertine deck around the pool, on 4" of crushed rock and 2" of sand on top of that. The pavers are 1 1/2" thick.
My question is, what should I backfill the trenches with to fill the voids, pack it down and avoid any settling? The PB is suggesting sand.
Thanks for your help.