DHS's new BioLab at Fort Detrick, Maryland, is hobbled by a series of flaws and glitches which have prevented researchers from moving into the facility years after it had been dedicated; the most serious problem was the placement of valves that allow access to HEPA filters in biosafety level 3 lab; the filters must be decontaminated or replaced every few years, but the valves to let workers into the air ducts were too far from the filters