Egon said:Will the topsoil effect the intended operation of the mound. My knowledge is limited to knowing mounds do not like compaction.
No. Mounds around here (Central PA) are the standard. As long as you don't plant trees, drive HEAVY Equipment on it or build anything on it, they are fine. I only want to take some slope out. Had a neighbor who filled in around his to make his whole yard level, he now has to pump his tank out every year becasue the sand mound cannot drain (ground around it hold too much water).