FEMA camps and the executive order are old news. The EO is Ford's (1976) and the FEMA camps were for WWII.
You are thinking of the internment camps, not the FEMA camps. From what I can gather, the FEMA camps started in the 1980's. Some more info can be obtained by googling “Rex-84”, “NSDP51” (also known as “PDD51”), “HSDP20”, “H.R. 645”.
Originally, the red herring was that the camps were for a mass influx of immigrants. Now the red herring is just in case there is a biological attack there are now camps to quarantine people.
I have heard they are renovating some of the old internment camps for the FEMA camps.
FEMA Concentration Camps: Locations and Executive Orders
Critics Fear Emergency Centers Could Be Used for Immigrant Round-Ups- This mentions a contract awarded in January of 2006 to Kellogg, Brown and Root, a subsidiary of Halliburton, to build “temporary detention and processing capabilities to augment existing ICE (Immigration Customs Enforcement) Detention and Removal Operations (DRO) Program facilities in the event of an emergency influx of immigrants into the U.S., or to support the rapid development of new programs”.
And the shocker: Civilian Inmate Labor Program