Inspectors have discovered mold growing in heating and air conditioning ducts of the $1.2 billion U.S. Strategic Command headquarters under construction at Offutt Air Force Base.
The discovery of the mold, in September, has halted further work on the HVAC system in the massive structure, said Matt Bird, senior project manager for the U.S. Army Corps of Engineers, which is overseeing the job.
Other work continues at the 80-acre construction site, he said, but the mold-infested sections of ductwork will have to be removed. Military officials say the contractor, not the government, will have to pay for the extra work.
“It will likely have an effect on the construction schedule,” Bird said. “We’re trying to keep the impact minimal.”
Mold is present in the air and generally is harmless. But when it finds food, moisture and a place to colonize, it can multiply to the level that it causes harm to people with sensitive respiratory systems.
“It gets collected inside the ducts,” said Kent Rawhouser, president of the Indoor Air Quality Association. “You’ve got wet insulation, with dirt in there, and mold.”
What caused the mold to grow is still being investigated, Bird said, but it’s assumed to be linked to the dirt blowing around the worksite combined with damp weather in the months before the discovery.
“We just had a really wet summer,” he said.
When the mold was discovered, Bird said, the corps conducted air quality tests inside the building. The tests showed mold levels no higher than normal, and the corps allowed construction to continue on everything but the HVAC system.
In the past few weeks inspectors have sent remote-control cameras through about 4,000 of the 15,000 linear feet of ductwork already installed in the building to try to determine the extent of the mold infestation. Bird said they expect to finish examining the ductwork by the end of the month.
“That’s a lot of ductwork to inspect,” Rawhouser said.
The survey isn’t completed, Bird said, but so far about 5 percent of the interior of the ducts has been found to contain mold. It was found in ducts awaiting installation as well as ducts already installed.
The white mold is on the black rigid fiberglass insulation that lines the inside of the ducts. Rawhouser compared it with dandelions putting down roots in a lawn.
“When it grows into the insulation, it’s virtually impossible to clean,” he said.
The building contractor — a partnership of the Omaha-based Kiewit Corp. and Colorado-based Hensel Phelps — is still working out a plan to eliminate the mold and make sure it doesn’t recur, Bird said.
A local Kiewit spokesman declined to comment, deferring questions to the Army Corps of Engineers.
“We are working with them to address this solvable issue,” said Tom Janssen, a Kiewit spokesman.
Bird said it is certain that the solution will include tearing out all sections of existing ductwork where mold is found.
“Cleaning the ductwork isn’t a viable option,” he said. “Removal and replacement is pretty much where you have to go with something like this.”
Rawhouser agrees with that approach.
“They’re doing the right thing,” he said. “I would take my hat off to them for taking the steps that they are.”
Until the scope of the problem is known, it’s not clear what the cost will be to fix it. But military officials said taxpayers won’t be footing the bill, because the Kiewit-Phelps partnership is obligated in its contract to install ducts that are clean and free of mold.
“It won’t cost the government more,” said Steve Callicutt, StratCom’s primary overseer on the construction project. “It’s going to cost Kiewit.”
Rawhouser said mold typically isn’t discovered in a building while it is under construction. More commonly it is found after a building is occupied and people start to develop health problems.
He said engineers are fortunate because the necessary cleanup is less difficult in an unfinished building.
Workers broke ground on StratCom’s new headquarters in October 2012. Bird said construction is 60 percent complete. The target date for turning it over to StratCom is Dec. 27, 2016.
That date has slipped three months from projections made in February.
About half of the project’s cost is in critical electronics and communications gear as well as other furnishings that will be installed after the building is turned over. StratCom officials expect to move about 3,500 employees from the current headquarters by 2018.
In an effort to keep to that timetable, Bird said, Kiewit, Phelps and the Army Corps are juggling work schedules.
“We want to provide a facility that meets the needs of StratCom,” he said. “It just takes time to work through the problem.”
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