There's some documentation on an actual Hole Opening GM event.
http://everquest.allakhazam.com/db/item.html?item=55583
http://everquest.allakhazam.com/db/item.html?item=55584
The actual event was called "The Hole Uncovered." (lol)
Several items were handed out, one of which was this -
http://everquest.allakhazam.com/db/item.html?item=2120
Lore-wise, the Hole was sealed in order to quarantine a contaminated section of Old Paineel, where a ruptured planar portal was spewing out massive amounts of elementals from the Underfoot. The series of books should tell you pretty much what happened to break the seals.