This kind of non-disclosure suit is generally viable (for the amount in question, your attorney is probably going to try to help you get a settlement through early settlement negotiations or mediation as opposed to pushing the matter through an expensive trial), but you can probably get something out of it.
The hard part with any fraud claim is proving that the individual had actual knowledge (the seller is the primary defendant here, not their realtor, although they usually end up getting sued too). However, with soil compaction issues there are usually very obvious signs of defects that arise that would put the seller on notice (cracks in stucco, concrete, misaligned doors, cracks in interior drywall, broken windows (in severe cases), etc. that would at a minimum put the seller on notice that there is an issue.
You can find local attorneys using the State and local Bar Association directories, or private directories such as www.AVVO.com; www.FindLaw.com; or www.Martindale.com (I personally find www.AVVO.com to be the most user friendly).