Lee,
A couple of things jumped out at me, a landowner. First, the chemicals. If you address that in the agreement, I think as landowner, I would want veto power over any chemicals prior to their use in the ponds. Also(as landowner), I would agree to not harm the pond in any way, but would reserve the right to treat my property with chemicals as needed for my purposes.
The other item was firearms...may not be a problem, depending on landowner, but I would not permit firearms as a landowner myself. My ponds are too close to my house.
Just my thoughts. I think you are doing the right thing by writing it down; you won't be sorry.
