Apparently my ex wife (as if I needed another reason to be angry at her) allowed a neighbor to use the saw some time ago while I was out of town. He didn't clean off the sawdust. Why the leaky bleach bottle was placed on top I'll never know.
Bleach is a powerful oxidizer, and it took 15 minutes with a nylon scrub pad on the ROS just to get the caked, rusty sawdust off.
But now I've got these huge black stains on the top that will probably never come off.