Yes indeed, you can make a soundtrack station on Pandora.
However, your station won't just stick to music from the soundtrack; it'll have the music discovery aspect just like regular stations.
To make the soundtrack station, just pick the songs from the album that you like, and create a station from those song titles. Obviously, thumbs down any songs you hear that you don't think belong on the station.
There's a bunch of sample soundtrack stations here: http://rurl.org/ubi
Try some out and see what you think!
Also, it sounds like you like orchestral soundtracks. We are in the process of improving our classical / orchestral soundtrack collection, and we're adding new albums every week. Expect orchestral soundtrack stations to get much better over the next couple of months, as we continue to beef up our collection.