The insistent, gnawing buzz that emanates at all hours from the Terrorist Screening Center in Vienna is scheduled to be significantly reduced by mid-August, and perhaps reduced to the sound of a normal building by next spring, according to a letter from a General Services Administration official to members of Congress.

Neighbors near the building on Follin Lane have been tormented by the high-pitched buzz since before the building was occupied in 2010. Twenty-three air-conditioning units on the top of the building are responsible. The owner, Goldstar of Bethesda, the landlord, GSA, and the tenant, the FBI, all made promises to Vienna town officials to reduce the noise. They didn’t.

But a letter sent late last week to Rep. Gerry Connolly and Sen. Mark Warner by the GSA’s regional administrator, Julia E. Hudson, says reducing the number of air-conditioning units running at night “will reduce the noise level by about one-third,” though she added, “with the exception of extremely hot weather events.”

Goldstar is making further fixes to the cooling system, and the GSA will install a water-based cooling tower to “dramatically reduce the need to operate the existing rooftop HVAC units that have been the source of the noise problem,” Hudson wrote. This will take six months and “will result in the elimination of almost all perceivable noise from the building,” Hudson added.

Neighbor Ken Foley, who helped lead the neighborhood charge and has met with a screening center administrator, said, “Whether it turns out to be an effective and permanent one only time will tell, but I for one am tickled pink with the development.”

I’ll be adding more here from key parties throughout the day.

Here is Hudson’s letter:

Betsaida Alcantara, a spokeswoman for the GSA, said that “GSA and the new head of the agency took the concerns of the community very seriously. We've also worked with elected officials who have also raised concerns. We're glad that in conjunction with the FBI and the lessor, Goldstar LLC , we were able to identify both a short term and a permanent solution to the problem.”   

Connolly, who met personally with GSA Administrator Dan Tangherlini to try to resolve the matter, said Wednesday, “I’m happy our long national nightmare is over.” He said it was “a frustrating issue, trying to get the attention of the landlord and then get GSA to focus on it.

“I’m hoping we’ve struck a balance here,” Connolly added, cautioning: ”Time will tell.”