In the new USFK Strategic Digest it has a really good break down on how the USFK relocation plan is going to happen that everyone following this topic should check out.  Here are some facts and figures from the report related to the relocation:

The ROK-U.S. Alliance is currently in Phase 1. The U.S. has reduced the force by 8,000 personnel and closed 18 of 31 camps. The U.S. has expedited the return of 16 of the 18 closed installations, returning over 12,800 acres to the ROK. In turn, the ROK has completed the purchase of over 2,700 acres of land, directly supporting the U.S. relocation. The ROK government has granted an initial 912 acres of land at USAG Humphreys, enabling the ROKU. S. Alliance to begin designing, planning, and coordinating over $10B worth of construction. The majority of the funds required for land, facilities, moving services, and other expenses directly related to the YRP implementation will be provided by the ROK, while the costs of LPP are to be shared between the U.S. and ROK.  Approximately $335M of facilities and infrastructure are under construction at
USAG Humphreys with an additional $2B of facilities and infrastructure under design. The major facilities that will be constructed are: medical facilities (hospital, dental clinic, and troop medical clinics); headquarters facilities (KORCOM, EUSA, 2ID, Installation Management Command-Korea); family housing and schools;
communications center; and the operational and support facilities necessary to relocate the 2ID.  [USFK]

Here is a graph from the report that shows how the phases of the relocation will happen:

Something I have to wonder is if a railhead of some kind will be built to get equipment up north to the Joint Warrior Training Center?  Can you imagine the potential for accidents if heavy equipment from the 2nd Infantry Division has to routinely conduct convoys from Camp Humphreys all the way up to this training center?