Congrats to him! Does he have a preference among the schools you previously mentioned?
His top three are Cal, Michigan, and Purdue.
Texas A&M, Illinois, Tennessee, and Georgia Tech are all in that tier just below. I'm not sure of his ranking below them. For the grad program rankings, A&M is something like 8th nationally for nuclear engineering though, so it's definitely a strong contender in that tier.
He's also applied to Stanford, and is planning to apply to UCLA, UCSD, and Cal Poly-SLO. I *think* based on wanting to go into nuclear with aeronautical/aerospace engineering as a fallback, they might be below the tier mentioned above due to not being as strong in nuke. However, in-state tuition might be important if he misses out on his top 3. Stanford, if he's lucky enough to get in, would probably be out of the running. They don't have nuke, and while they obviously have a strong aeronaut/space program, he wouldn't be going there unless he's getting a BOATLOAD of scholarship aid.