When tearing down bases on private property, the goal is to return to the land as much as possible to its previous state, Katers said. But even bases that are being turned over to Afghanistan for official use require U.S. engineers to modify them. That may mean tearing out wiring designed for U.S. electricity standards and removing things such as expensive-to-operate water and latrine systems that the cash-strapped Afghan government won’t be able to maintain.

The building boom at FOB Apache and similar projects elsewhere are all about holding down costs and making it easier for the expansions to be torn down in just a few months. That means that designs meant to last five to 10 years are gone. For Apache now, the standard is good enough to last a season. The housing is mainly tents on wooden decks, which will be cheap and easy to remove. Showers and latrines are in trailers.

Apache has grown so fast that it’s burst beyond its walls, leaving older guard towers in the middle of the base rather than on the perimeter. Its population of 800 to 900 in December grew to a few thousand starting in January, said Army Capt. Tyjuan Campbell, who oversees base operations and is akin to the mayor of a small town.

Expanding a base so quickly in the middle of a pullout has presented odd challenges, said Campbell, who’s with the 3rd Infantry Division in Fort Stewart, Ga. One issue has been drawdown-related rules that make it hard to bring in more contractors to help get the second dining hall running and maintain the additional generators needed to operate a large camp.

And even with creative thinking by the managers of the lone chow hall, who expanded seating and went to 24-hour service for sandwiches to ease the crush, there are long lines for every meal.

Members of the 181st Engineer Company of the Massachusetts Army National Guard, which is part of the 555th’s task force, arrived four months ago to take on what was supposed to be three weeks of work. Campbell begged them to stay, and they’re still at it, said Staff Sgt. Ricky Wolff, of Beverly, Mass.

Among other projects, they renovated building shells for several unit headquarters, more than doubled the size of the fire station and built a second residential area, with dozens of tents. They built a camp for interpreters and have nearly completed the recreation center. Still to be done: a major addition to the helicopter pad and floor platforms for another neighborhood of tents, to house hundreds more soldiers.

Supplies and equipment are hard to find this far from the larger bases, and the engineers of the 181st have resorted to a military tradition: scrounging. They root through an unmonitored supply dump where materiel had been building up for years and they’ve even dug through the trash to find electrical and plumbing parts they need, Wolff said.

So much of what’s going up is simple and basic that the guys in the unit, who include master carpenters and master electricians from civilian life, were happy to get the job of building the recreation facility, which also is in a tent but requires a fair amount of interior construction.

Wolff, who’s on his sixth deployment, was involved in similar projects during the drawdown in Iraq.

"In a strange way, it’s kind of nice to be around for the last hurrah," he said.