What's wrong with "špinavý vlak stoji na nádraži"?
"Špinavý vlak stojí na nádraží" is closer to English sentence "The dirty train is standing at the station."
However, this sentece needs revision - the verb "standing" shouldn't be there twice :-)
Yes, it definitely shouldn't be there.
Also, I think the "there is" is very confusing when you try to translate into czech and not necessary at all. A better English version would be "A dirty train is standing in the station"