The claim: two compounds: Rex 84 detention camp and FEMA detention facility.
What it really is: First let me ask this: why would there be two different detention camps run by two different groups, especially when they're doing the exact same thing? It makes far more sense to have one compound run by one group.
Anyways, the army base itself is huge, and contains nearly 13,000 people there at any given time, and is used to train up to 80,000 troops there annually.
The base also has a large amount of housing for military families, and employment opportunities for civilians as well.
The base borders several towns, and several other towns actually have parts of their townships within the base itself.
Considering all of this, it would be pretty hard to hide one prison camp there, much less two.