I happened to stumble across this board and have an interesting question I'd love to ask.

I will be stepping back into the college radio booth next term and wanted to be able to bring with me a large collection of music (on iPod or portable hard drive) without having to lug around the CDs. (From there they'll be played off a computer.) So I want to ask:

To what quality does radio broadcast?

Seeing as radio has limited quality (...right?), what format of music file can I use that is about the same as radio quality, or something that is not too far from it? Is radio quality far greater than mp3 and many lossy codecs out there, or are they closer to radio, and thus the reduction in quality is less perceptible?

Obviously I am sure this all depends on the equipment a station uses (to which I have no clue what is operating at mine yet) but if I can encode my music from CDs and save some space at the same time I just want to make sure I can crank out the best ratio with little or no quality reduction

It depends on your storage capacity. But if you only intend to use your backups for radio broadcast and storage is limited, I would suggest Ogg Vorbis -q 4 for your purpose.
[edit: oops mistake]

The degradation would be most noticeable to someone who records off the air then re-encodes to mp3 or other lossy format.

Even recording a talk show to mp3 (at a low rate) I have noticed that the anchor's voice sounds clear but some sound clips or the voice of someone maybe talking over a compressed link (or using a voice recorder) will sound degraded compared to when I heard it straight off the radio.

That encode-decode-encode cycle is the quality killer.