Just what it says - depositing materials on your own (or someone else's) land in violation of the law. Since these laws are quite local in nature, I can't answer specifics even if you had given them. What is illegal in one area may be permitted in another.... more
When it comes to any safety/crime related issues, it's always best to contact the local police department with all your questions, hear all there is to hear firsthand. If unfamiliar with the area(s) do revisit more than once and at different times of day, possibly chat with locals/neighbors. Real estate professionals are prohibited from steering, enticing a buyer to purchase/rent, or not, in specific neighborhoods.