I'm sure the water is boiled via the fire then cooled with new water to a comfortable temp. Atleast it looks like the fire is only smoldering maybe enough to maintain temp. I'm sure the boiling kills anything leftover from the previous soaking.
You would need a BIG fire to get that all water to boil.
Besides that, oil, dead skin and other stuff doesn't get removed just by boiling.
I'm sure the water is boiled via the fire then cooled with new water to a comfortable temp. Atleast it looks like the fire is only smoldering maybe enough to maintain temp. I'm sure the boiling kills anything leftover from the previous soaking.
You would need a BIG fire to get that all water to boil.
Besides that, oil, dead skin and other stuff doesn't get removed just by boiling.