The bacteria that cause Legionnaires' disease have been found in the drinking water there.
And that's not the only concern in that building.
It was routine testing conducted late last month that revealed the disconcerting news that the very pollutants the EPA is tasked with protecting people from had been found in their employees' drinking water.
As of now, there are no reports of Legionnaires' disease being diagnosed among the government employees based out of the Metcalf Federal Building in the Loop.
But concerns are rising, after it was revealed two weeks ago that several of their drinking water sources had tested positive for the bacteria.
"It's not only Legionella, but also lead and copper. And there is no safe level of lead," said Loreen Targos, with the American Federation Of Government Employees Local 704.
According to the General Services Administration, which manages the building, the contaminants were found in kitchens and water fountains distributed among five different floors, three of them occupied by the EPA.
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Union leadership has now filed a grievance against the agency, which they accuse of not acting quickly enough to fix the problem.
"Legionella is dangerous when it becomes airborne. So, our bathrooms are now a hazard. We want to be able to work from home until they are capable environment to work in. Right now, that's not happening," Targos said.
An EPA spokesperson said "EPA leadership is committed to ensuring that all its staff work in a safe environment."
The spokesperson went on to say employees have been provided with safe drinking water as the General Services Administration continues to develop and implement remediation plans.
Employees said they've seen some messaging on the issue, but not nearly enough.
"Certain areas of the building you'll see signs that say, you know, 'do not use,' or something to that effect and they are being addressed. That's what we are told," said Francisco Arcaute, with AFGE Local 704.
Union officials said that is not enough because not all the fixtures within the building have been tested.
The EPA acknowledged receipt of the grievance, but declined to comment on the specifics.