The septic tank holds the waste and bacteria break down the solids and what can't be broken down settles on the bottom of the tank. The liquid flows into the drain field where it is absorbed into the soil. One thing to remember is have the tank pumped every 3-5 years as the solids build up and reduce the capacity of the tank. I have read it is not a good idea to have a garbage disposal on your kitchen sink others say its OK.
good idea to have a garbage disposal on your Green house sink' makes the compost happen quick .. PLUS . Ever fall after grow , flip 6-8 " and add the ground up compost !! S
New tech showing for either new or rework of septic systems' Replacing A Leach Field | Styrofoam Septic Drain Field Cost And Install - YouTube