I am an excavator by trade and I am going to be building my first vinyl liner inground pool. The house I live in backs onto a ravine with about three to four feet deep of topsoil in the back yard. I need to raise the height of the pool a couple feet to match the grade at the house. In doing this I may only be digging a couple feet deep into the ground to get to the proposed elevation for the floor of the pool where the pool will sit. This could leave still a couple feet of topsoil under the elevation of the pool. I know when I do excavations for basement foundations we cannot put walls on top of topsoil. I guess what I am asking is should I remove the remaining topsoil from under the pool and fill it back up with some sort of aggregate or sand to the height of the bottom of the pool and compact it before doing the concrete floor for the pool?
Thanks in advance,