Also what could be the potential repercussions of this?
Well, you have publicly posted on a high traffic social media site that logs IPs and connects them to your username. If you didn't disable the click tracking, they might have a more detailed profile of your activity than just IPs. You have had the account for several months so it is almost certain to at least have a personally identifiable IP address attached to it and logged permanently in a way you can't delete it.
You also posted to a high traffic legal focused subreddit frequented by LEOs (law enforcement officers).
So, let's see what the consequences of your post are so far. You have confessed knowledge of:
1) The sale of drugs in violation of federal law.
2) The storage, possession, and intent to distribute concentrated narcotics. Concentrate is treated differently than flower.
3) Interstate drug trafficking. (Obviously a federal offense.)
You are obviously not in a good position here because this post has already been archived so deleting it won't do you much good.
Your risk comes from knowledge and proximity. If it is your roommate, that is different than a friend you see once per week on the weekend. Remember: We are talking about you OP (original poster) /u/wenisance. We aren't talking about anyone directly involved with it, selling it, processing it, storing it, etc.
If you live with a roommate that is involved with it, use it yourself, and have some in your room when the police come knocking, it might not turn out well for you.
Your friend should get another job. You should keep your distance as much as possible. None of you should do anything without a lawyer except get as much distance as possible.
DO NOT TALK TO THE POLICE FOR ANY REASON OF ANY KIND BEFORE TALKING TO YOUR LAWYER!!
That is the most important part of this post. If the cops show up at any point, say you invoke your right to remain silent and say nothing else. You don't answer questions. You don't respond to their provocations. You don't listen to your parents saying you should come clean. You only listen to your lawyer. If you don't have one, ask for one. Demand one.
tl;dr None of this is good. Get as far away from it as possible. Your friend should do the same. Serious consequences follow this type of stuff.