I wanted to build a hoop house, but I need to be able to drive stakes or 1 5/8" pipe into the ground to hold the hoops (pvc or 1 3/8" top rail.) From all I have read, these ground pipes or stakes need to be 2' in the ground. The problem is I am on a septic system, and I don't know if there are lines I could be driving the stakes/pipes into and breaking my septic system field lines.

Is there a way to secure a hoop house other then driving posts into the ground? I considered a greenhouse on piers, but I don't think it will be secure either. Foots are probably too permanent and require permits.

The problem is the wind on any of these structures, as I see it.

Edit: The ground is clay. I could probe it by slowly putting a stake of some sort in the ground. I am guessing if I hit gravel, stop, move over, try again?

Edit: The hoops will be top rail fencing and will be bent at the time. They are then put in the post in the ground and have a bolt through both pieces and a wood frame along the bottom.

Edit: It is at the bottom or near bottom of the leach field, and I don't know if I could hold the structure down with sandbags. I can look at it. I have a lot of cinder blocks sitting around.