Kirk Freeman
Grandmaster
This has already been suggested, but it helpful to see it in photos as we are males and learn by seeing, but the solution is to increase the height of the berm, install bullet roofs (prevent rounds from striking berm and flipping out of range), put a fence up on top and aggressive blue sky elimination, see page 14: http://files.dnr.state.mn.us/destinations/shooting_ranges/outdoor_shooting_best_practices.pdf