Yes. The process of deterioration happens to concrete tanks. Gases build up in the septic tank as a result of the decomposition of waste inside the tank. More solids present in the tank will mean more gases present in the tank, resulting in more rapid deterioration. Over a period of years, the gases inside the tank slowly start to eat away at the surface of the concrete. This process occurs above the water line in the tank and will affect the top of the tank. Concrete below the water level is usually not affected. As the process takes it course, the surface areas of the concrete become rough and start to crumble away. Slowly, larger pieces begin to break away. Eventually, the rebar or steel inside the concrete, once used for strength, will rust away. As the process continues, the concrete loses its strength. At some point, as the concrete weakens, the lids will collapse if not repaired or replaced. Pumping removes the waste in the tank which reduces the amount of gases in the tank. This means that more frequent pumping can greatly slow down, but not eliminate, the deterioration process of the septic tank. Over time, some deterioration of the tank is inevitable.