Jim,
There are huge amounts of land under the RR act and a huge amount of claims being held to this day by different RR's. On those I always call the regional BLM office to see if the area is still under RR. Do not be surprised if nobody knows what you are asking about either.
I could give you more than a dozen examples where there is RR land, no tracks and was never on the table to track an area. Last time I called BNSF it took them a month to track down the RR land and the only reason they did was that the person I was talking to had no idea about RR act land and wanted to learn.