Dumping
My wash had a big dumping problem before I owned it. I added cameras and caught some offenders including one who was legally forced to pay me $400 as restitution for my labor and materials for cleanup. I also keep the wash as clean as is reasonable, whatever that means, as a clean wash seems to more discourage dumping compared to a dirty one.
The cameras detected that only a few residents were responsible for a majority of the trash problems. I captured their plates with a camera, used zabasearch or other tools to chase them down, and politely told them to knock it off. The dumpers always immediately cease dumping trash after I contact them, and, oddly, not a single one has ever asked how I identified them or chased them down.
Trash problems are frustrating, and when you catch someone and track them down it is tempting to get in their face about it. I do the opposite-- keeping very polite-- and explaining they were accidentally caught while me and the Sheriff's deputies were looking for the "real culprits" who are dumping hazardous waste into the dumpster. This keeps the discussion from turning confrontational and the addition of the word "deputies" seems to always add a bit more influence in their willingness to pay attention.