Hello! I've had a 30x15 oval above ground for about 4 years and just this summer I've noticed the back wall appears to be leaning out. I placed a four-foot level on the ground, touching the top area of the pool wall, plumbed the level and I see the bottom of the pool is 4 inches in. When the pool was installed, they used patio blocks on the ground, to rest each of the four angled side supports on. Then they filled dirt around them. Over the four years, it seems more dirt filled in around the base of the support so I didn't notice whether it was sinking. I'm guessing that's what is happening, the patio blocks are slowly sinking further into the dirt. We are in a very sandy soil area along the NJ Jersey shore. Here is my plan - does this sound logical? I'm draining the pool almost all the way, then digging out around the four back supports. While they have no weight against them, I thought I'd dig a 1-foot hole where each support meets the ground and place a cardboard tube filled with concrete. I'd make sure to plumb the side of the pool and mark where the support should meet it before pouring in the concrete. And perhaps insert some sort of brace so it's protruding from the concrete. Being a construction amateur, does this sound ok? Thanks in advance! Bill