Thank you and I understand what the term means but there is generally never a substantiation of a case and then a mediation. Generally mediation comes before
the EEOC even investigates the case or makes a decision about whether or not they think the case is substantiated.
The reason why I asked you about whether the EEOC had said they were going to keep the case and file suit or issue a "right to sue" letter, is because that determines what happens next. This page is the EEOC's statement of the process of charge handling: http://www.eeoc.gov/employees/process.cfm
If you are just now going to mediation, then both parties must agree to it and nothing is binding on either party. In other words, you and the employer can agree to a resolution and settlement now, or simply walk away and then litigate the case.
If the EEOC decides to take the case themselves, which they will tell you if they are going to, then they will file suit on your behalf and you will simply be a witness and have to participate in depositions, like a regular law suit. If,during litigation, the employer makes a settlement offer, you will be consulted regarding acceptance or not of the offer.
If the EEOC decides not to file suit on your behalf, then they will issue you a "right to sue" letter and you will have 90 days to find an employment law
attorney of your own to file suit against the employer.
Please let me know if you have any specific questions I can assist you with. I would be glad to do so.