My first reaction was that, if the lot can't be built on, then it may have little or no commercial value. If that's the case, are you sure you want to hold onto it?
Still, if you feel that it has value, or the state is offering too little, then contact a good real estate lawyer. Each state has its own procedures for seizing property and for determining the value it'll offer. It's often very difficult to stop the seizure, but you often can increase the amount being offered.
Hope that helps.