dumping gray water in forest

We registered into a National Campground in Northern AZ. and the attendant said our totally full gray tank couldn't be dumped because his tanks were full. They had it hauled out. He then said it would be ok to dump it at the site. I felt guilty so I drained it in buckets and distributed it in different parts of the forest. The next day there was no sign of my dump. When we desert camp I always dump in the desert because the cactus may not see moisture for months. The amoeba brain before us dumped his black tank. We camp in an area where we may not see another camper for a week-end but even there it's possible to incur a subhuman species that would defile the desert.
The real problem, that these sub-human vacuum brains that communicate with grunts, are allowed to vote...:(