I'm in the process of being recruited and I was given a questionnaire for national security positions. I'm guessing this is for clearance, as the MOS I want requires secret clearance. I have nothing to hide, but my only issue with this is that I'm a very introverted person with no friends.

I can probably get 2 classmates and a family friend (I'm not really close with them) to let me put them as my 3 references for people that really know you.

At what point during the recruitment process do the investigators actually begin going through your clearance information? Is it after you have chosen a job at meps or before?

Also, for secret clearance, is it certain that those people will be talked to and will I get a heads up when they are going to be contacted so that I can let them know that I used them as references? I don't want to tell them I'm going to use them as references if it turns out that I choose a job that doesn't require clearence. However, my recruiter is asking me to complete the clearance forms asap.