We have to remember, this happens EVERYWHERE, not just at the border.
These people are right too. Many of the pictures of the trash at those sites are sporadically taken all over the southern part of the state and, no, it isn't mostly from illegals.
There are tons of out of the way areas near the border that have been local teen party hangouts, illegal trash dumping from Americans such as refrigerators, tires, sofas, ect ect. Some of things they found during the clean up in 2007, when that video was made, was an old 1950's fridge, curtains, condoms, used oil dumped, broken toilet, bags of household garbage, beer cans, soda bottles (glass ones), and the list goes on and on. Now, do you see an illegal taking the time to back pack a fridge or old toilet to dump it on their way into the US?
Also, where much of it is dumped is in a dried river bed. When the rain comes at night, in most cases, those small river beds can become raging rivers within minutes which carries much of the trash and such down the way. They have had to clear dams of garbage in the refuge and protected wildlife areas for years. That area has been used as a dumping ground and party place for over 40 yrs and very few people ever paid attention to it and kept dumping.
This can be said for many states all over the US. In my state they used to have a problem with people dumping old tires and furniture in local creek beds in residential areas. There were some places where people would hang out and party at night in wooded areas and leave their trash and even underwear in those areas, till they were blocked off a few years ago. This is not only an AZ issue when it comes to this type of careless distruction.
Edit: And for the record, I gave no one a thumbs down. But oh well, apparently the truth is not what people want to hear.