I picked up a Radon test while browsing in Home Depot. Just thinking that it might be good to see what the concentration was before I bought expensive radon vent fans and sealed up the sump hole. I followed the instructions and left the two small vials uncapped and placed them in the living space over one of the vent pipes. I had to keep the doors and windows closed for 4 days which was not difficult in the cool and damp days of early May. After exactly 4 days, I capped the two vials and registered them on a website then mailed them in with a check for $30. (Didn’t realize the $10 test would require an additional $30 lab fee.)
In a surprisingly short amount of time, notification of the completed radon report was emailed to me and I was able to log into the site to get the full report. We definitely have a high level of radon present in the house. The test showed 23.7 as an average of the two vials, which were 20.7 and 26.7. So what does that mean? The EPA recommends a Pc/L level of 4 or lower, 10 or higher requires mitigation.
I found that Jefferson county makes tests available for $10 but it is not clear if that pays the lab fees. Kansas State manages a National Radon Protection Services website and they advertise $15 all inclusive short term kits and $25 long term kits. First you have to register with the site to order a kit. But unlike the commercial test, you can pay online with a credit card.
Radon is a cancer causing agent and there are odds for both smokers and non-smokers to develop cancer as a result of exposure. At 20 pc/l the odds are 36 out of 1000 non-smokers could develop lung cancer (260 smokers). So radon mitigation is definitely required and I’ll purchase and install the fans on our slab depressurization system.
Additionally, the soil in the crawlspace will have to be covered with cross linked polyethylene sheeting and a pipe from under that cover will connect to the existing passive system with the addition of a fan to that pipe. In all we will have three or four fans venting radon gas. Two underslab vents, one crawlspace, and one in the sump area.
Next the water will have to be tested. There was a big puddle of water on the floor from a burst hose during the test and that may have contributed to the high level of radon. Radon mitigation for well water is much more expensive than soil mitigation. The preferred method is aeration, running the water through nozzles in a large tank and blowing the contaminated air out of the upper part of the tank. The other is a carbon filter, but the radiation accumulates in the carbon and can itself become dangerously radioactive.
There is no correlation between the existence of radon in the soil and in a well, nor any correlation between the depth of the well and the existence of radon. It will be interesting to see if we got a double-whammy of radon. (UPDATE: No radon was found in the water samples!)