"The source must be capable of providing transportation from virtually any hospital in the United States to one of a number of designated receiving facilities. The source must be able to respond to potential requests within six hours. It is expected that these transports would be within a reasonable distance to allow for safe, ground transportation. In some instances, these transports may be from a sending facility to an airport location"
The key insight from the above quotation is that the Ebola outbreak is expected to be large enough that it cannot be handled by air ambulance transportation to 1 or 2 centers in the United States. Rather, the expected number of Ebola victims is large enough that multiple Ebola "receiving facilities" will be setup to be within a reasonable safe Ambulance driving distance for the majority of the USA.
Should such an Ebola outbreak occur in the USA, such regional Ebola concentration centers may be helpful when outbreak numbers are low. However after exponential infection growth rates start occurring, such centers are more of a place to die than be treated.