Re: a septic tank is small
I know the term 'cesspool' which is probably the same in practice and meaning as cesspit.
We were renting a house (rural community), built but not finished but the price was right.
It was beginning winter but there was still some of the original summer garden growing
which was a gift, given that it was over 50 miles to a decent store with veggies.
There appeared to be a piece of plywood on some of the land (without plants) and I thought
to move it and see if the soil could be worked and seeded with peas for the spring.
What I saw was....undigested (not enough bacterial activity to work on waste) sewage. There had been enough activity to keep it warm (hence the growing plants).
I realized where the seeds for the plants had come from and became sick immediately.
We had not been told anything about this situation and the owner said we should have asked.
He had hoped to sell the property to us. The place stayed vacant until he got a proper permit
from the county and installed a septic system.
What that entailed in a rural area was a large tank which would contain the waste, digest it, and the fluid which rose to the top would flow into a leach field where it would percolate into the surrounding area.
The house was 40 miles from the county seat (NOT the area with the good stores) so the owner/builder had thought he'd get by doing things himself and sell it before someone found out.
In California there is the 'grandfather' rule which is that what was acceptable at the time of construction would continue to be acceptable until alterations or additions were made.
Consequently, those in the outlying areas knowing that building inspectors did not leave the county seat looking for code violations (often off the grid and on poorly maintained forest service roads) so that if violations were found, the owner would claim that it was grandfathered in. Used plumbing & electrical parts were in demand, often sold at flea markets or scavenged from the local dump.
And the cesspools/cesspits? Since there had been more than adequate land available when the original houses had been built (acres), after a period of time, another pit would be dug, the pipes rerouted, the pit topped off with stones, wood waste, etc. and a tree planted in the middle of it.
If you saw a magnificent tree where other plantings weren't so large or healthy, you knew what was there before.
Even way back then (well before our time there) people had understood the grey-water/brown-water
split so a leach field for grey water was only noted so the soil wasn't disturbed.
The Irish have an expression about 'bad cess to you' (ill-wishing someone). Makes me think they might have used the term 'cess' for a pit or pool as well.