You do not have to be a former Navy nuke to work at a power plant as an HP or deconner. Just ask all the non Navy commercial nukes that are happy to tell you that. College is up to you, again you do not need a degree to get started. What your Navy job was and the amount of time doing it will be evaluated to determine how much work experience you will be credited. You will have to pass a physical, you did not say why you were disqualified, but be sure you fill out your application papers for any job honestly and accurately. If you falsify your application and get discovered you will lose your security clearance. That follows you to the next site where one of the first questions will be, "Have you ever had your security clearance revoked?"
Good answer is always an honest no, saying yes because I lied on my application does not contribute to building a good resume.