Alright guys, I'm having a hard time deciding on a spray for a walking path that is surrounding a detention pond. I'm worried about leaching because the closeness of the pond to the path and the path is elevated above the pond leaving a 10' wide downgrade leading into the pond. The 10' downgrade is covered with Low Mow prairie grass. I know of the normal sprays like Roundup, Trimec, and similar. My question is what is the safest application to minimize run off and leaching into the downgrade covered with Low Mow prairie grass?