A credit check will show all past and present lines of credit you have been provided, which should include student loans. I'm not sure how far back the credit report will go, 7-10 years maybe? You can check your own credit for free, I'm sure you've seen the commercials. Any delinquent accounts that you are not currently making payments on will look bad, not sure if it will effect your ability to gain access. I'd highly recommend contacting the lender and setting up a payment plan or a debt consolidation loan of some sort. At least that will show that you are working to resolve it. The plant you are applying to may very well request you do so prior to granting you access.
Since your request would be an Initial Access, I believe that the background is 5 years or until you were 18. I could be wrong on that, it's been a long time since I filled out an Initial PHQ.