On inspection of one septic tank we found the sanitary line coming from the house (Inlet) going into the septic tank. The seal was broken, water was coming from the house or ground water was entering from the broken seal. This would need to be repaired.
When buying a house you should get a written report along with pictures of the septic tank and field on the property.
This inspection should include the sump pump in basement ( if there is one) And where the ground water is being pumped to. (This should not be pumped into the field).
Also this lets you know how well the septic tank is working.You will need to know the size of your septic tank, the condition of the walls & divider wall. This will show the amount of deterioration in the tank.
The written report will tell you if this system is a gravity fed or pump out system.Both these systems get the effluent to your septic field.The reports lets you know of any problems the tank or field might be showing, that may need to be repaired or replaced.
In another tank we found electrical wires were inside the septic tank and spliced together ( Not recommended)