Construction on servicemember housing towers continues at Camp Humphreys, South Korea, Thursday, Dec. 10, 2015. A $10.7 billion project that will see the bulk of U.S. forces in Korea concentrated at Humphreys by 2017 is 86 percent complete, a South Korean defense official said.

CAMP HUMPHREYS, Korea — The massive Camp Humphreys expansion project, which will allow the bulk of U.S. forces in Korea to shift there by 2017, is 86 percent complete, officials say.

“If the program were to progress at the current rate, it would be completed in 2016. Most of the relocation will be finished in 2017,” Kie Soo Kim, director of the South Korean Ministry of National Defense’s U.S. Forces Korea Base Realignment Office, told reporters Thursday.

The nearly finished 8th Army Headquarters where Kim spoke was evidence of significant progress this year on the $10.7 billion project, which has been called the largest-ever for the U.S. military.

The relocation originally was scheduled to take place in 2008 but was delayed until 2012, then to 2016 before the most recent timeline was issued.

U.S. forces on the peninsula today are scattered along the Demilitarized Zone and exposed to an immediate threat from nearby North Korean troops, Kim said.

Moving them south will increase their survivability, while Camp Humphreys’ proximity to Osan Air Base, the Port of Pyongtaek and rail links means troops there will still be able to mobilize quickly. Meanwhile, reinforcements and supplies will be able to arrive quickly in an emergency, he said.

U.S. 8th Army commander Lt. Gen. Bernard Champoux, who spoke alongside Kim, said a major milestone was reached in July when the perimeter of Camp Humphreys was extended to encompass much of the new construction.

The fence movement added 1,200 acres to the base, doubling its size, officials said.

“We are constructing hundreds of new buildings and adding 2,000 acres to this installation,” Champoux said, adding that the Camp Humphreys population would grow from 12,000 to 42,000 with around 2,700 command-sponsored families once the project is complete.

Some residual forces will be left behind north of Seoul, at least temporarily, and a small command presence will stay at a downsized Yongsan Garrison in the capital.

Positioning forces south of the Han River will have no impact on their readiness to respond to a threat from North Korea, he said.

Asked about the possibility that the North might target troops concentrated in one place, Champoux said U.S. forces employ protection measures wherever they are based.

“Our forces north of the Han have them, and we will have them here,” he said, adding that Patriot missile-defense batteries will be in place.

This week, officials held a rehearsal for the movement of units and agencies from bases in Seoul and near the DMZ next year and in 2017, he said.

“This is a very complicated plan,” Champoux said, noting the need for his forces to maintain readiness while participating in exercises and rotating units from the U.S. during the move south.

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