Belt is dead, the dirt eroded the crap out of the groove sides to kill all grip. As well much dirt likely still stuck in belt carcass to make it slip even more. You ain't going anywhere without a new belt and then go from there, the tensioner may be dead too from dirt getting in it, they are not weather sealed. The pulleys with that much dirt may even have impacted it in the grooves to build the groove depth shallower and then all pulleys will need 100% of the concreted dirt chipped out before they will properly grab the belt again. You can look hard at the pulley and not see that and then the belt makes noise forever. The concreted dirt will appear to be part of pulley and requires extreme force to remove it.
thanks so much, i dont have any time during the week to do this, so ill definitely do it this weekend when i change my oil. thanks for the tips!Also, i have replaced both idlers and the tensioner on my '09 VQ already and I just hit 100Kmi. When those bearings go (and I'm sure the sand might have helped them along) they start to wobble and that will definitely cause a squeak. So with the belt off, spin each by hand and check for smooth silent operation. There should also be some resistance...ie they should stop soon after and shouldn't continue to spin long after being spun, that's indicative of bearing wear, often accompanied by a tinny rattle.
What tools would i need to take the belt off/chip the dirt off the pully/idlers? flathead screwdriver, knife, socket wrench?
thanks for the help, this is my first car and im trying to keep it running for as long as possible... then ill swap the engine