(EDITED TO ADD:
Mystery solved! See update in message #9.)
This one is a new one for me. I think we received a "stinky" passive-aggressive message today. I think it's probably best to politely ignore this unless/until someone speaks to us directly. But, I'm interested in what others here think.
Background: We live in a subdivision that is way out in a rural area that is becoming a far, far outer suburb of a metropolitan area. Houses here have a minimum of one acre of ground. I think that is partly because there is no public sewer system, and the only kind of septic system that is allowed for new construction is aerobic/anaerobic systems that treat the waste in underground tanks then finally spray the treated wastewater out over the yards.
Our underground tank that holds the final treated wastewater before it is sprayed out has a hopper inside where we place chlorine tablets every month. The system is tested by a licensed inspector four times a year. We have passed every test - including the one in late November.
Today: When I was out walking our dog this afternoon, I noticed a colorful little cardboard container beside the far side of our house, on top of a plastic box right under the electrical controls for our septic system. I went over to look closely, and it turned out to be two little cardboard packages of a chlorine bleach based toilet bowl cleaner. It looks like the packages are still full of their contents. They'd be too heavy to have just blown in on the wind (and, besides, they were on top of a plastic box, not directly on the ground); so I'm pretty sure someone deliberately placed them there under our septic system controls.
I guess this could be a strange random "gift" from someone who no longer needs his or her toilet bowl cleaner.
But, since it contains chlorine and it was left right under our septic system controls, I'm thinking it is more likely to be some kind of PA message about our septic system.
Since I know our septic system passes its tests (and, indeed, I added the monthly chlorine at the start of December), I think the best thing to do is ignore this until someone speaks to us directly about it. I'm really curious to know what others here think, though...