[SIKSUKR]

I question whether a failed septic is any harm to the lake if it stays contained in the system itself. When a septic fails its usually the leach field which clogs or collapses not allowing the effluent to leach into the ground. If the system doesn't leach at all and your tank becomes full and needs to be pumped frequently without overflowing, it would be my contention that the surrounding ground is LESS effected by waste water. It would work like a holding tank. Of course if the leaching media is clogged and the effluent tends to run somewhere else like towards the lake then that is an issue.