My understanding (BOD may chime in if they so wish) is that the 23 acres (yes, that is correct) encompasses the ROW and all of Clark parcel to the west of the ROW, and a buffer to the east of the ROW.
This includes the hunting camp on the back portion. The parcel meets (at a corner) land owned by the Sheepscot Valley Conservation Association.
I do not believe the museum has any immediate plans for the property. Although, is nice to have a large parcel that is only accessible by rail, for future museum activities, events, and more.
I will note will great joy that I have created this "official work thread" for our northern expansion. (And I merged in some older, related, topics.)