Glad to see that someone is taking notice of shrinking areas of natural 'quiet' noise; and attempts to keep some records of their incursion into other habitats that are precious.

When out in the 'wilds' of Alaska, the obnoxious racket of unmuffled & unregulated
aircraft, some of these flyers are businesses & make a fair living; training 'mountain & lake take-off and landing' as part of a floats certificate they're allowed to sell pilots.

Since FAA nor other regulators will intervene when these sometimes overpowered loud under-muffled aircraft wheel about senselessly for hours, over pristine valleys where their racket echos off the mountains for miles, one thing the prudent outdoor lover, be it hiking, hunting, nature photography, wildlife studies, & so on, can do is make note of the plane's identification and hours of operation on those days. 

Instead of citing an unregulated noise factor, the prudent can record, take images, & file safety complaints. FAA will investigate those. ;)