What does an 'ice run' means in Heathers?

There is this scene in Heathers (1988), where Veronica and JD sit in her car discussing a murder they commited the night before. Veronica is upset by being fooled, but Jason reassures her it was all for good. After that she asks him if they could make an ice run before funeral.

Veronica: God!

JD: Football season is over, Veronica. Kurt and Ram had nothing to offer this school but date rapes and AIDS jokes.

Veronica: Sure… Could we make an ice run before the funeral?

He then shrugs and answers positevely. I considered a drug reference, but it doesn’t seem to fit in the movie. What can it possibly be?