Do whatever you are comfortable doing for each and every employee that ever works for you from this day forward. Because whatever you do, since this is the first time it has happened to your company, sets a precidence. What you do for this guy, you will have to also do for the jerkwad that has only worked for you for two months and has been a screwup since day one.
Make sure you don't TELL the guy anything. Write it all down, discuss it with him, and have him sign the paper outlining your discussion. Have someone else that is as nuetral as you can find, sit with you both and just listen and take notes. The third party does NOT take part in the discussion.
You can certainly give him whatever benefits he has earned thus far. He can use that time and money to go to court and attempt to get a judge to give him to/from/during work driving privileges.
Explain to him that you may be sending him for random drug & alcohol testing during his recovery period and that you and others will be watching him closely for signs of screwing up again. You MUST have all this in writing because if he gets involved in a traffic accident while on the job, the other parties lawyers will learn of his record and come after you, your family and everything you have.
The earlier advice given about not telling anyone is absolutely correct and essential. You may pick one other person in your company, preferably another manager, to be the third party. But you cannot, must not, under any circumstances, discuss this guy's situation with anyone else.
Yes, Joe Blow is having some problems, but we are working with him to work things out. I suggest you speak with him if you want to know more. Now please get back to work.
It sucks, but it's just how things have to be nowadays.