Seems to be a problem in poopular areas. They've even just built 2 toilets, Roman style, at Corrour Bothy because human contamination of the hill streams was making it unsafe as a water supply.
Looks like you must use one of the special bags (degrades at 40 DegC), otherwise the system doesn't work. - Problem if the Ranger Base isn't open when you arrive at night for the walk-in. How do you pick up the special bags & bottles? (Carefully, I dare say
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