Jul 30, 2016
From https://www.extension.purdue.edu/extmedia/id/id-170-w.html which explains the setup for septic tanks and leach fields.
Note, the outlet to the field often goes to a “D-box” to send effluent out to separate leach lines (depending on capacity of the septic tank and percolation rate of the soil, differing lengths of leach line are required).
This shows a diagram of the septic tank.