esshup, those tests were all performed on my kitchen countertop and I just didn't remember to circle that one since it was a separate 48hr test, rather than a 10sec-3min test like the others. Sorry for the confusion!

Thanks for the tip. I'm in a residential area, and we've been having plenty of rainfall. No cows, but could be our dogs, I suppose. My main question is whether it is cause for concern if I were to swim in it.... which I already have! laugh

Kris