RDAP stands for the Residential Drug Abuse Program. It is a federal Bureau of Prisons program, meaning it exists specifically within the federal prison system and is not available at state facilities under that name or with those exact benefits.
For federal inmates, RDAP is one of the most valuable programs available. Completing it can take up to 12 months off a sentence and guarantees six months of halfway house placement on the back end. That combination makes a significant difference in real time served, and for eligible inmates it is worth pursuing aggressively. Qualification requires documented evidence of a substance abuse disorder before incarceration, typically through medical records, prior treatment history, or court documents, along with a conviction that meets the program's eligibility criteria. Here is a link to their Inmate Handbook.
For Minnesota state inmates, the situation is less clear cut. The Minnesota Department of Corrections does offer substance abuse treatment programming, and some states have developed their own residential treatment tracks that carry sentence reduction benefits. Whether Minnesota's version provides early release credits comparable to federal RDAP is something that needs to be confirmed directly with the facility's case manager or through the MN DOC website, as program details and eligibility rules change and vary by institution.
If your person is in the federal system and housed in Minnesota, RDAP availability depends on the specific facility. Not every federal institution runs the program at all times, and waitlists are common. Getting on a waitlist early is the most important step for anyone who qualifies.