A question about alcoholic ex-husband?

My ex and I have been divorced for 4 years. He is an alcoholic, in denial, and refused to get help. Many people in his family tried to talk to him as well, and it did no good. We have 2 daughters, ages 8 and 5 that I have physical custody of. He takes them on overnight visits every other weekend. My Mom and I are always watching him to make sure he doesent appear intoxicated, both at pick up and drop off. He will come over with his clothes stinking of booze alot of times, but he appears fine so I just figure he must have been drinking earlier in the week. Anyway, this weekend the girls had Girl Scouts and it was his weekend, so he dropped them off at the meeting and hung around. I was there, too. He seemed his usual self, so I didnt think anything of it. Then later this evening, one of their Troop Leaders called to tell me he reeked of alcohol when he stood near her, and it concerned her because he drove the girls. But she said he appeared ok, or she would have asked him to leave. I gave her a little info about our situation, and told her I would talk to him. I decided to take him to Court to have Visitation ammended, because obviously he's doing some drinking when they are in their care. We already have a Case pending in January bec he insists on taking them to a married friend's house to play with their 2 boys, ages 8 and teenage. Often they spend the night. I don't like it, and have told him many times to stop, but he refuses. I don't know why its so important to go over there, I believe partying is going on, my 5 yr old doesent even want to go over there, either. And to make matters worse, his friend is dying of cancer! I don't think my girls should be in this position, he gets nasty to me and constantly bad-mouths me to the girls, upsetting them. I want to know if I can request an Emergency Hearing on this issue, since he takes them again in 2 weeks and thats before our Court date. I just don't trust him to take them anywhere now. Also, what kind of proof would I have to give to the Judge to prove he's got a problem? He's a functional Alcoholic.