How long for under-slab to dry out enough to restore proper suction? Long-term concern
Edit: I did the math, since it's something I'm reasonably good at, and it's far more clear than 'probably fine', 'not the worst', and other subjective summaries. Based on the lifetime risk matrix, which shows about a 0.1% chance for non-smokers to get lung cancer over a lifetime exposure of 70 years at 6 pCi/L, that translates to about 0.0014% added chance per -year- of exposure. A few weeks is something like 0.0001%
SE Wisconsin. We've been getting utterly dumped on with rain and the ground is super saturated. The area under my slab got way more saturated than it ever has before due to a pump not getting power for a day or so, and even caused some small puddles under my carpet (terrible idea by former owner) that are now dry. The unfinished part of the slab is very slowly drying out, even with two dehumidifiers running (finished + unfinished space).
My pCi/L which has stayed very consistently between 0.3 and 1.0 in the basement for 99.99% of the last few years but is currently reading about 6.0 on the first floor for the last few days. Opening windows for a couple hours gets the pCi down to safer levels and then it creeps back up over night when they're closed. My radon system is currently reading about 2 on the manometer when its normally closer to 1.
I know this should go back to normal once it can finally dry out... but it's April. Does anyone have any experience in how long to expect this to take? The technician in this post said late summer, but I don't trust that perspective coming from someone trying to make a sale.
Furthermore, I also see posts (again, from someone trying to make a sale, i think) talking about groundwater being able to permanently change the geology under your slab so that re-mitigation is necessary... I have little kids, and I don't want them breathing in toxic air for months while I 'wait it out' to see.
I can call the company that did the mitigation years ago, but I expect them to use fear tactics to make a sale as well.