Extruded Polystyrene Pool Base

[jzcop]

Hey everyone, i'm installing a 15x30 oval pool in New jersey. I have 1 inch thick Extruded Polystyrene sheets for the base. I compacted the direct base with a plate compactor level which was an 18 inch to 0 dig out to get the ground level. I am going to backfill the low side after installing the base and pool. I was thinking about adding a root barrier like a 18 mil plastic sheeting or tarp, used for under concrete slabs under the XPS sheets. Would this be a good idea under the XPS? Is there anything else i need to do for a good stable XPS base?

Thanks in advance for all your input.

 

[cowboycasey]

1 thing that we almost never recommend is back filling, with that said if your using a plate compactor and done right by layers you may not have a problem, but it is still a possibility it could sink, that pool holds about 110,000 pounds of water I also dug down 2 inch on the south side and 24 inches on the north side and compacted screenings 2 inches deep, I still had settling... go figure

I did not use any plastic sheeting or barrier but I have 0 trees and no grass what so ever under mine

 

[jzcop]

the back fill would be the overdig trench on the on the low side and not the base. Just wanted to make that clear thanks