Septic System

Today the new septic is going in.  The former owner of this house decided that he would drag his feet and wait it out.  This is because he knew that it would be a mess and he would have to have it cleaned up before we moved in.  They kept telling us the reason they are waiting is because they didn't want to rip up the ground.  They of course decided to do it when the ground is saturated so all of the big trucks are getting stuck.  Does anybody know what that does to the ground?  Anybody, Anybody.  It is now not only too muddy for my dogs it is also going to be hazardous for my kiddos.