Do I need to re-test for radon after landscaping?

Question

We moved to a new house recently and are having some major landscaping work done in the backyard (removing/relocating a number of boulders, flattening out one area of the yard and filling another in, etc.).

Before we moved in, we did a radon test and the results came back very low (I think it was 0.4 pCi/L). However, I've read that the amount of radon in your home is very specific to your individual house (e.g., your neighbor's house could have much higher/lower radon that yours does).

Therefore, I was wondering if big changes to the surrounding landscape could cause the radon levels to change significantly. Should we do another radon test after the landscaping work is complete?

Answer 1

As a parent, I can see the reason for your concern.

Radon is a radioactive gas. While a bit could be released by landscape work, any radon gas would be in the open and therefore readily disbursed. The only potential problem would be if the area you worked sloped down to the air intakes for basement ventilation and if you are in an area that rarely has wind: radon is a very heavy gas, and if there is no air movement it could concentrate in a low spot.

Remember that if radon is found in a basement the treatment is increased ventalation. Your backyard has lots of ventilation.