more research was done by Lex and Cadmus Labs in concert with Fort Abrams, since it is near Smallville.
This is what I get for just watching seasons 8-10 and Clois-related bits.

Well, to be fair, I'm stretching this a bit as well. I could imagine that Lex had military projects, and Fort Abrams is implied to be very near Smallville. So thought it was only a small leap to make it the place that Lex may have had some Kryptonian related research lying around...