Having mananged a government organization where all my employees were required to have a national security clearance, here is my view.
You will be asked to fill out a security questionairre prior to their conducting the actual background investigation (BI).
A standard questionairre will usually ask whether you have any old, unpaid delinquent debt.
If you do, be sure to answer truthfully, as they will see it if and when they pull your CR, and a false statement in your questionairre will either lead to a denial of clearance, or if you do receive a clearance and they discover it later, a revocation of your clearance. Deceipt is a death knell for any security clearance.
If you have not paid the debt, chances of approval will most likely be slim. Thus, I agree that you should satisfy the debt prior to the clearance process.
If it is paid, it may or may not affect approval. That is dependent upon their current guidelines relevant to the type and level of clearance. Having been honest and having paid the debt might get you through. Having let it go to the point of charge-ff reflects upon your character, but is no longer a potential for outside coercion, so it is mitigated. The fact that it was years ago may also mitigate any reflection on your current character
As they are likely to pull your CR and become aware of it in any event, my recommended course of action would be to make an initial call to the security office of the government organization that will be administering the clearance process, and ask them if the presence of an old but now satisfied debt will be a show-stopper.
Only they can tell you if that is an absolute basis for denial.
While I have no govt affiliation and cant comment on the others advice I can offer a suggestion reguarding these accounts I know you say ASAP how long? When you contact these CA's or OC's first they will be thrilled to be getting paid on the old debts and in full at that! Use a little negoitiating and try for pay for delete. It also wouldnt hurt if they agree to ask if they can send off the request to delete while still on phone (dont deal with a low level collector request a supervisor). Of course get this also emailed to you A that you paid and B that its requested to be deleted. Then join one of the CR monitoring services that allow daily pulls. You might get lucky. If its not a deal beaker on security clearence and you get PFD's you will be helping your credit score. Good Luck!!!
I have been in Navy Recruiting for the last 17 years and withholding information for your clearance is a huge mistake. I would make contact with the creditors. If you have the money do a PFD. If nothing else works you can try to contact the OC and see if they will turn your CO's into an installment loan of some type to remove the CO. With some of the Clearances if you show that you are making payments they will be satisfied.
Hope this helps and Good Luck