Security at the facility is intense. The Baltimore Sun was granted a tour of the facility on the condition that no photographs would taken beyond the lobby. Visitors are not allowed to enter labs, even those that are not being used, to ensure that they remain in pristine condition should they be needed.

The air leaving the facility is scrubbed through filters, solid and liquid waste is boiled in pressure cooker-like machines and the building itself is designed to withstand heavy weather. Interstitial floors between the work spaces allow crews to control utilities coming into labs without actually setting foot inside.

The redundant safety measures, of course, don't entirely allay concerns by some in the community — many of whom recall a time when similar work was carried out with less caution. Detrick was home to the nation's biological weapons program from the 1940s through the 1960s, and groundwater contamination from some of the activities on the base has been a problem for years.

An independent panel of scientists from the National Research Council concluded last year that there is no way to tell whether the groundwater affected the health of people living near the base.

In another troubling case, five people were killed and more than a dozen were injured by anthrax sent in letters to Congress and news organizations in 2001 that the federal government alleges originated with Bruce E. Ivins, a scientist who worked at the Army lab at Detrick.

Ivins died in an apparent suicide in 2008 as the FBI prepared to charge him in the case.

Peter Herz is a member of the Containment Laboratory Community Advisory Committee, a seven-member group appointed by city and county officials in 2010 to facilitate communication between the labs and the surrounding community. He also lives near Detrick.

Herz, who stressed he was not speaking for the committee, said people with whom he has contact have mixed feelings about the lab.

"We hear from a lot of community members who are concerned about the presence of dangerous material — and there's a lot of mistrust," Herz said. "But, to be fair, there's also a lot of people who value the scientific and technological base that the laboratories bring to Frederick."