T., you're thinking of a
septic tank ~ it's designed to ferment and break down the solids and usually has "leaching" pipes radiating out from it that have holes along their bottom part so as to allow the liquid to seem out and settle .
(lord I worked on/in/with and installed a lot of those in rural New England in the 1960's....
) .
Old dry wells were often concrete, brick or rock lined then filled with large stones, only ground water run off was allowed to go in , no sewage .