[jeffrow1]

We recently filled in our pool for most of the same reasons as the OP. We removed gas, electrical and plumbing. Bottom was broken up along with 2-3 ft of sidewalls. We filled it with 60 tons of road base followed by 12" of topsoil, I can't imagine having a "swamp". The biggest issue we had was trying to incorporate the existing concrete decking into a new landscaping plan.