That the vault has two levels is described in an article at https://web.archive.org/web/20080313134302/http:/www.bxmagazine.com/article.asp?ID=265 -[INDENT]
The most important feature of any bank is its vault-and the two-story, 12,000-ton, 3,560-sf Cleveland Fed main vault is second to none in the world. The door alone weighs 300 tons. The 100-ton swinging section is precision balanced to allow a single person to close it. When closed, the door is held by 16 steel bolts, each 6 inches in diameter and weighing 246 lbs. The 47-ton hinge casting is almost 19 feet long and reported to be the largest hinge ever manufactured. The vault actually occupies a “building within a building” constructed before, and separately from, the remainder of the facility. The concrete walls of the vault “building” are 6.5 feet thick and reinforced with interlaced fabricated steel. It would take an ambitious safecracker indeed to take on this formidable opponent.
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However, there is no indication of a second door. If there is just the one door, you’d have to guess there is a heavy elevator in the vault.
