Ranger:
I understand your issue quite well. I'm in the enviro field, and know the risks...and that they are actually quite small, from any individual home. The reason most states are trying to do away with direct discharge septic systems is that, as they are quite common, the aggregate of the discharge is big. I think it's unfair to impose these restrictions retroactively...Iowa allows homes to be grandfathered. No large changes and you don't need to retrofit. Major work or bath additions and you need to go with a sand mound or similar. It's quite expensive, and beyond the means of many. That's why most don't even bother to tell the county officials when changes are made...
In a lifetime, the average driver will honk 15,250 times. My wife figures I'm due to die any day now...