Answer to your question: The worst area I saw for pollution was at the end of a brutal 8mi hike that included a few thousand lost/gained feet in order to finally access a %^&^$#!! polluted lake shore that is a one thousand foot descent (bye-bye hard work..)One could hike in or horseback ride in. The pollution was caused by squatters who had been there who knows how long (squatting is a by-product of zero supervision of the area)
Okay, outta here -- have at it!
That's a really tough one, Bee. I see no way to fix that problem with permits or supervision. Luckily it's very rare, I think, or maybe I've just been lucky not to see it.
There is one way to almost guarantee a remote wilderness experience - get off the trail with the quota. Break out the map and compass and pick a bearing to a destination of your choice. I've had several lakes all to myself even on a July 4th week including northern Yosemite not far from a very popular backpacking lake destination. Not one fire ring. Not even fish, but then again I'm really bad at fishing so maybe they were there.
People seem to like to hoard up in groups and go to the same place every year. If you think about it, you can take advantage of that part of human nature and either participate with them if you want company, or be glad they're all there and not where you are in the back country. It's not that hard to get away from the masses and 99% of them don't want to be alone in the wilderness.
But can anyone guarantee you not to see another person? I think that is asking too much of our government.
