When it rains, sewage water is saturating our back yard. It smells, so I guess one of our neighbors called the health department. They guy from the depatment said it sounds like the pump in the septic tank is pumping too hard. I don't know much at all about septic systems and I don't have any idea how to adjust the pump to flow less. There is a foot and a half diameter plastic cap on top of the tank and I am guessing that is where the pump is accessed. Am I most likely right? Can someone please post a good diagram showing and describing the operation of a residential septic system? Thanks!!!