Tim Dominick/The State

The Third Army will cut the ribbon on the George S. Patton Hall today at Shaw Air Force Base in Sumter.

COLUMBIA -- The military men and women who supply and support U.S. Army forces from Iraq to Afghanistan move into their new $100 million home today on South Carolina's Shaw Air Force Base.

The move marks the formal shift of 1,200 military personnel and their families from Atlanta's Fort McPherson. It was ordered in 2005 by the Pentagon's base closure and realignment panel.

The Third Army is in charge of logistics for Army forces from Iraq to Afghanistan. The move puts them alongside the Ninth Air Force, in charge of all air forces in the region.

The shift is expected to pump about $120 million annually into South Carolina's central region, local leaders said Thursday.

Two years of construction has turned a scrub pine forest into a complex of campus-like buildings with a 320,000-square-foot headquarters named in honor of Gen. George S. Patton, the legendary World War II leader.

Army soldiers used to working in 50-year-old windowless buildings are dazzled by the new building's soaring foyer, huge windows and high-tech facilities, said Third Army spokesman Col. Jerry O'Hara.

"Everyone's walking around with 'new house' smiles on their faces," O'Hara said. Equally surprising has been the warm welcome given the soldiers by the community, as "Welcome Third Army" signs have sprouted for months around the nearby Sumter community.

O'Hara noted that the Third Army is in charge of planning and supplies for the 200,000-strong Army force in a 20-country region that stretches from Iraq to Afghanistan.

The command is weighted with senior officers, most at a major level or above who earn around $80,000 annually, said Ike McLeese, president of the Chamber of Commerce for the greater Columbia area.

He said the $120 million economic impact figure was conservative and that many of the military officers who serve in the unit also have working spouses who will add to the economy. "This is a big win for the region," McLeese said.

About 300 Army men and women have already made the move, with the remainder headed to South Carolina over the summer months after the school year wraps up, said a former Ninth Air Force commander who is the executive director of a Sumter-based group that works on military-civil issues like housing and helping military spouses find employment.