It is always a good idea if there is nothing provided, to early on research the property yourself, either by physically walking all of it or at least using Google sattelite to see what is on the property or around it.
If there was no disclosure, it can probably be addressed as an inspection item.
You need to discuss it with your attorney. If you are out of attorney review, you might still be able to get out of the deal. If you are still in attorney review, no problem getting out.
If you are not out of attorney review, and the seller has signed, you will need an attorney to x the contract, or delay it from being finalized. That is very easy to accomplish, but you must act quickly.
If the seller has not signed, you can retract the offer through your REALTOR and further investigate the easement before moving forward.