Power steering belt jumping off

[SupraDupra]

Drove my supra to work today and when I got into the parking lot I dumped the clutch and laid a patch accross the lot ,and my power stearing belt liberated itself from the pulley.I put it back on and proceded to try and turn out a doughnut ,this time I broke the belt.This is a brand new belt and there is more than enough tension on it - has anyone else had this problem? Are there pulleys with deeper grooves available? On my second attempt I wound up pointing at a company truck without the power stearing and my PCV filter popped off and stuck the throttle up (Clutch in ,shut down ).So I need to address this issue.