Depends on what "disposed of properly" means. As far as I understand it, if it's not leaking, then it doesn't require any special handling like asbestos. But I found the page you got that quote from, and their links have various standards for how to dispose of them.That's what I do along with the bulbs.
I have never heard of that. If they are not leaking then properly disposing in your trash is no issue.
As per epa.gov:
PCB-containing ballasts become a concern if they are leaking or they will be removed and disposed of as hazardous waste. According to EPA Toxic Substances Control Act (TSCA) regulations, the material must be incinerated. The entire lighting fixture does not need special handling and disposal as long as the ballast (electrical box) is not leaking. The non-leaking ballasts can be removed and recycled or disposed of properly.
I saw Maryland in one poster's info, and apparently the state says that ballasts with PCBs should be properly recycled. This is pretty nasty stuff so I'm not sure if tossing it in the trash is a good idea. But I have a place that will take them.