The other site in the running was adjacent to Fermilab in Batavia, IL. It would have cost much less to build there, because it would have used the existing ring as a pre-accelerator, and the human capital necessary was already in the vicinity. Not only was it going to be more costly to construct in Texas, it would be more costly to maintain as well; I recall something about the insect population in Texas being much more detrimental to the concrete.
This was all being planned and organized in the 1980s, and I think Bush being Vice President (and then President through 92) may have had something to do with it going to Texas.