Let me start out by saying I live in south Florida. I have herited my family home and I am in the process of trying to fix it up. My father about 30 yrs. ago decided to have excess soil from when a new drain field was installed spread across our swale. Over the years this soil which was full of rock and pieces of drain field tiles has compacted so solidly that nothing but weeds can grow there. I have tried using a tiller and broke it. I want to excavate the swale down about 12-16 inches and replace the soil so I can sod the swale. We have very severe thunder storms as well as hurricanes which can flood our streets for a day or more. Any recommendations on how and what to replace this soil with to give me good drainage as well as a good foundation for grass and landscaping as well as an ocassional car parking on it.