no, the problem will continue.
radon is unhealthy so only replace the noisy fan with a quiet one.
search for radon at energy federation:
http://www.energyfederation.org/cons...th/30_406_1304

46erjoe wrote:
Just bought our home 4 months ago. It tested positive for radon (but
just barely). The seller agreed to install an active radon reducer
fan-type. It runs all the time, sucking air from under the basement
slab. After recent testing, the radon leven was very very low.

I see is that there are many large cracks in the floor. Around the
outside edge runs a gap at least a quarter inch. Then there are
several shrinkage cracks also very large.

If I were to seal every one of these cracks with urethane calk and
thus make the basement airtight, would the radon problem go away?

Or can radon leach through concrete block and floors? I sure would
like to shut off that noisy 24-7 fan and convert it to a basement
bathroom vent to the outside.