How long does it take for Roundup to leach into the water table - 200 feet down? Does it harm living "things" on the way down? What is the danger to animals who eat the sprayed weeds? Are you supported by any chemical manufacturer?
I'm afraid these questions are out of my expertise. Much research has been done and continues to be in the forefront of environmental concerns.
We are not supported by any chemical manufacturer.
I have listed a few links for you, but the list of research that is available is very long.