Ever have to replace a divider wall in a concrete septic tank?

[Leaffan]

@Weisshund

That might depend.
Mine will bubble if the covers are not under dirt, even if bone empty.
But mine is not gravity fed, there is this huge nasty grinder pump in a concrete box that pumps everything up into the septic tank, and the fitting inside where all that nice stuff goes is a T, one side points down the other up right at the cap.

If you take off the cap while the lift station is in motion there is a 20 foot tall shit geyser that you better run from.
I learned this the bad way

Ah yes, macerating pumps. Required when the bathroom loo is lower than the tank.