On the edge of a tree-lined Vienna neighborhood, there is a constant, high-pitched buzzing sound coming from an unmarked three-story office building. You’ve never stood next to such a loud building. It has been happening for nearly two years now, and the neighbors and Vienna town officials are at their wit’s end.

A sliver of forest does little to mute the buzz on Mashie Drive or Niblick Drive or Alma Street, in the neighborhoods just east of Route 123, back behind the Anita’s Mexican restaurant. It sounds like a helicopter is hovering about a block away — a helicopter that never goes away. It just keeps buzzing, 24 hours a day.

The noise is caused by 23 “dry cooler” air-conditioning units on the top of the unmarked building, each with 10 fans, for a total of 230 high-velocity whirring noises. It’s not loud enough to drown out conversation, but it’s annoying enough to make you say, “What IS that sound?”

The building is owned by the Goldstar Group of Bethesda. “They’ve always said they would be good neighbors,” said Steve Briglia, the increasingly exasperated town attorney for Vienna. ”The town is extremely frustrated that it’s taking so long to address the neighbors’ concerns.”

The buzz “comes through my double-pane windows, with my air conditioning on full blast at night,” said Ken Foley, one of the neighbors who has been pleading for sonic relief since August 2010.

Now here’s the part that may or may not be relevant, but is awfully interesting: The building’s only tenant is the FBI’s Terrorist Screening Center, the place where they compile the no-fly list and other important national security data. There is, undoubtedly, a lot of heavy-duty computing going on in there which needs to be kept cool while running around the clock.

The building on Follin Lane has three flag poles recovered from the World Trade Center out front, and a sculpture made from the Twin Towers’ wreckage in the back.

The building’s previous tenant was the CIA, and neighbors say they were, unsurprisingly, quiet. The agency vacated the roughly 200,000-square foot building years ago. Goldstar, together with Transwestern Commercial Services of Chicago, bought it and the 18-acre lot for $25 million in 2005.

In 2007, the FBI decided to relocate the Terrorist Screening Center to the lot, and call it Liberty Park. The property is two blocks from Orrin Street, where two of the Sept. 11, 2001, hijackers lived in a rented house for a time before the attacks.

An architectural rendering of the Terrorist Screening Center in Vienna was submitted last year to obtain approval for two memorials for the Sept. 11, 2001, attacks. The air conditioning units on the roof were omitted from the rendering. (Hickok Cole Architects/Town of Vienna council records)

Initially, Hembree had refused to grant the FBI an occupancy permit to formally move in. But Briglia said Goldstar, the FBI and the General Services Administration (the landlord for all federal agencies) assured the town that if they were given their occupancy permit, they would work diligently to resolve the problem. Based on that good faith assurance, the town issued the FBI its occupancy permit in November 2010.

Not much air-conditioning is needed in the winter, and the noise died down. But it started again in the spring of 2011. Again, Hembree, Briglia and others pleaded with Goldstar, the GSA, anyone, to turn down the noise.

Meetings were held. Sound level measurements were taken, showing the din exceeded the town’s sound law at night. “We have been assured by representatives of the building owner that they will take steps to ensure the noise levels meet the Town Code,” Briglia wrote to Mashie Drive residents in May 2011.

Still, nothing. Goldstar told Vienna officials in November 2011 that they would devise a noise baffling device to surround the roof units, neighbors were told. Still, nothing.

The spring of 2012 rolled around, and the din resumed. More decibel testing by Vienna, while the outraged e-mails and phone calls poured in not just from neighbors on Mashie Drive and Niblick Drive, but from Alma and Orrin streets and further west toward Route 123.

“The hellish unending noise continues outside my window,” wrote Jeff Lewis.

“It is obvious,” Foley wrote in late May, “that we are about to suffer through yet another warm holiday weekend listening to this maddening noise.”

David Roberts wrote the noise is “resembling that of a propeller plane taking off in my direction -- of a nature that is psychologically disconcerting as well as being loud.”

Rep. Gerry Connolly (D) got involved in April and met with Dan Tangherlini, the acting head of GSA, and asked him to intervene. Two months later, he got a letter back from a regional administrator saying ”GSA is aware of the noise objections” and that the FBI’s lease requires Goldstar to comply with local noise regulations. But the letter said some new approaches suggested by Goldstar could reduce the noise enough.

Those approaches were revealed in a June 6 meeting involving Vienna officials, Goldstar, GSA and the FBI. Lynne Strobel, Goldstar’s attorney, reminded the group that Goldstar “maintains that the operations at the Property do not violate any ordinances of the Town of Vienna,” according to a letter she sent to Vienna Mayor Jane Seeman on Monday.

“However,” Strobel continued, Goldstar and GSA “have agreed to attempt to address the noise concerns to be a good neighbor.” That line did not go over well with the neighbors.

Goldstar said that it will test running fewer fans at night, when the ambient noise is less and the buzz carries further. And the fans that are running will operate on the southeast corner of the building, away from the northwest direction of the Mashie Drive neighborhood. The FBI also was testing modifying the fans on the dry cooler units, Strobel wrote.

Mike Hillman of Goldstar told me Wednesday that “we’re fully aware of the concerns over the noise. In efforts to be good neighbors to the citizens of the town...operational and physical solutions have been proposed by our engineer and we are optimistic that these changes will result in a meaningful noise reduction.”

I asked why this had taken two years. “There are a lot of parties vested in coming up with a solution,” he said, “and they are working to do so.”

I asked why they needed 23 air conditioning units. He thought it was the “nature of the facility,” but said he wasn’t an engineer.

Francis Dietz, a spokesman with the Air-Conditioning, Heating, and Refrigeration Institute in Arlington, the trade association of air conditioner and heater manufacturers, said that dry cooler air conditioners are often preferred over water-based air conditioners because they are less likely to freeze or break down when running at all times. Data centers and server farms that need to run continuously often choose them. Dietz thought 23 units on one building sounded like a lot, but he didn’t know the size or specific needs of the Vienna building.

I contacted both the FBI and the GSA multiple times to see if they really needed that many air conditioning units, and if they were going to help reduce the noise. The FBI wasn’t talking. On Thursday, the GSA released a statement that said they were “concerned about this issue” and were working “to resolve it as expeditiously as possible.”

Briglia said he was “guardedly optimistic...but it still seems to be taking too long.” He and the neighbors repeatedly said they were honored to have the Terrorist Screening Center in Vienna. But the center’s “operation is irrelevant to the noise being made by the air conditioning,”Briglia said.

In a town council meeting Monday night, Briglia said all options were on the table in terms of dealing with the noise, including seeking a legal injunction. But really, who wants to sue the Terrorist Screening Center?

The neighbors were not thrilled by the solution of simply reducing the din to the legal levels prescribed by Vienna’s circa 1950s sound ordinance, which uses outdated decibel and frequency measurement criteria.

“I have to remain hopeful, because it’s sort of a sanity thing,” said Craig Bradley, who has helped lead the neighborhood charge and has maintained a running dialogue with Hembree since 2010. In recent weeks, as the realization of another helicopter-noise-filled summer loomed, “people have really lost it. They’re sending blistering e-mails to the town council.”

And everyone is asking, “How are they able to do this?” Bradley said. He said neighbors have been patient but they’ve heard the “good neighbor” bit from Goldstar from the beginning. “And they've just been slow-rolling us ever since.”

This post has been updated to include the GSA’s statement about the situation, and to delete the reference to the 9/11 hijackers, which further research showed to be untrue. The Orrin Street residents had the same or similar names as the hijackers, but were not the hijackers.

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