Does anyone have cat 5 cable buried in the ...

umm not quite making sense of your overall situation , but yes they do have special cat5 cables that go outside or underground. Unfortunatly i cant give you specifics,at the office we call it outdoor cat5 cable, its thicker that standard cat5 and its black on the outside with a gel on the inside.Google it and see what comes up.I know it exists as im looking at it right now and we use it to mount outdoor ip cameras and such.

Just use cheap conduit to protect it.

Thank you. Regars

A nice shielded CAT 5 should work as well.