You're welcome. I have received a lot of help here myself. Everyone has something to contribute. I'm probably not a good one to ask about the trenching machine. Also, you may find advice with more research and experience behind it that says go ahead and go deep. Personally, I concern myself with providing a firm healthy playing surface in a variety of conditions, so I prefer to work in the upper 12"- 16". We're rarely deeper than 3" for any work once a field is in service unless it is to repair a sprinkler or dig a temporary basin to pull water from. I have had deep tine work done though and it is a mess when they hit something in the 8" - 10" depth they work in. Farming, I'm sure, is always better off deeper. Their implements tear deeper too. I meant to ask earlier, are you planning any electrical work such as field lights or a scoreboard? Good luck with this project. I'm sure the kids will appreciate your efforts.