One of our maintenance guys tracked in some "muck" he was working with on the roof and luckily only got one quarter sized spot on the carpet. Is there any way to get this stuff out?

Tar Removal from Carpet:
Spray WD-40 directly onto the tar. Leave it for about ten or fifteen minutes and wipe off with a clean cloth. You may have to repeat this a couple of times, but soon your carpet will look the same as it did before the tar was tracked in.

I had a city worker go into chamber quarters with road tar all over his boots. I used Fels Naptha soap. I scrubbed it with a scrub brush 3 times and it took it all out.

Try Goo-Gone, that's what I used after we had a similar thing happen here after a roof replacement.