Hey Scott, here are a couple more pictures, although they don’t really reveal much else.
When I took the actual, large, photos to the Denver chapter NACHI last week, two of the top area inspectors looked at them (separately, so they did not influence each other) and immediately said “Efflorescence.”
I spoke with Kenton Shepard on Sunday, and he is still not convinced. “No way of knowing for sure unless it is tested.” Which I agree with but will not upset these people. I will carry sample jars with me and get it next time. I have seen it before, just not to this extent. Which is another reason I am not buying your termite treatment theory. When I have seen it before it was more spotty, not entire ground cover. Also notice in one of the first pictures, it does NOT cover the sewer pipe. Very careful treatment appliers?
I don’t know. I’m just going to wait until I see it again (I thought I had it in my crawl space, but I don’t.) Get it tested somehow. I am still leaning to efflorescence, but you and Kenton are tough to convince!