My father is looking to replace his current outhouse and indoor toilet
(not particularly sound in any way, but grandfathered due to age) with
something more ecologically sound and maybe even legal. This is a cabin
that gets maybe 1-3 months' use a year, on a lake, in New Hampshire.
He's about 75-80 feet from the lake, and maybe 15 feet higher.

This would be something usable by a variety of relatives who visit
irregularly, and would not want to be trained in a complicated toilet,
carry urine to the garden, or anything else like that. On the other
hand, it doesn't have to be exactly a flush toilet for them to use it,
either. Gray water is handled with a French drain system, which seems
to be adequate.

We've looked at composting toilets, incinerator toilets (the neighbor
who has one of those said that it takes about 1/2 hour to cool down
enough to be used again -- a problem when there are children and old
people in the house), and a holding tank that would be pumped out
yearly. I suppose there's a cesspool, too, but that seems like an
awfully expensive option.

Ideas?

thanks
Wendy