The site is near Route 50 and Auto Park Circle
  

Unbeknownst to most residents, when the Fairfax County Board of Supervisors recently re-adopted its revamped zoning ordinance, zMOD, it quietly added a provision allowing data centers to be built, by right, on industrially zoned land within a quarter mile of residential homes.

To the supervisors, data centers represent a massive amount of county tax revenue. But for others, they sound the alarm for their potential to emit noise 24/7 and pollute the soil, air and water – including the Occoquan Reservoir, which provides safe drinking water for the county’s nearly 1.2 million people.

In Chantilly’s Pleasant Valley community, this threat is hitting close to home. That’s because PDCREF 2 Chantilly LLC (Penzance) wants to build a gigantic data center nearby. The site is adjacent to the Cub Run Stream Valley, Route 50 and Auto Park Circle, off Stonecroft Boulevard in Chantilly, just 4/10 of a mile from Pleasant Valley. 

The land is partly zoned commercial and partly industrial, so Penzance is asking the county to rezone all of it industrial. It’s also seeking special exceptions so the data center could be as high as 110 feet, instead of the 70 feet allowed there, plus have more density. A warehouse option is offered as a plan B, but it’s obvious to all that the data center would be much more financially beneficial to both the county and the developer.

It would arise on 12.1 acres of a 79-acre parcel, with the remaining 67 acres preserved as a Resource Protection Area. Representing the applicant, land-use attorney Evan Pritchard presented details of the proposal to a recent meeting of the Joint Land-Use Committee – Sully District Council and West Fairfax County Citizens Assn. (WFCCA).

“The site was approved in 2020 for a car dealership that was never built,” said Pritchard. “We’re proposing a 402,000-square-foot data center, but what gets built could be smaller. It’s large for that site, but not as large as some other data centers. And there’s stronger demand now for data centers, than for car dealerships.”

He said it would have a couple acres less impervious surface than would a car dealership and 46 percent of the 12.1 acres would be open space, including “a stormwater-management pond to prevent pollution from getting into Cub Run. And a data center would have far less daily vehicle trips.” Access would be off Auto Park Circle, with a Route 50 entrance for emergency vehicles only. And a 10-foot-wide trail could go around the Resource Protection Area.

Pritchard said the data center wouldn’t be visible from Route 50 or the Pleasant Valley neighborhood, only from the air. However, he added, “There’d be noise impacts from the generators and cooling systems. We’ll probably have air-cooled systems, but they do generate noise.” He said system maintenance would occur weekdays during daytime and downplayed the noise it would cause, but a resident said it could still disturb people working from home, napping children and the elderly.

A resident asked if there are plans to mitigate the sound if it exceeds approved noise levels, and Pritchard replied, “We’ll have to commit to noise proffers in the non-generator portions of the building where the employees are.” 

Civil engineer/architect Jamie Cox added that county Zoning Code Enforcement would respond to complaints and could cite or even shut down the data center.

But Pleasant Valley’s Cynthia Shang disagreed. “There’s no way for the county to enforce that or do anything about the problem of continuous noise,” she said. “The constant, high-pitched hum [from the roof-mounted chillers] can still be incredibly annoying to humans.” And a neighbor said it would be even worse in winter when the buffering trees between the center and homes were bare.

Josh Bowden, Penzance’s vice president of development, said it would take 12-18 months just to build the exterior. And Pritchard said they’d contribute some $108,000 to the Park Authority if the whole, 402,000-square-foot facility is approved. 

But the discussion didn’t end there; it continued at a June 15 meeting of Pleasant Valley residents. Since the data center would be built right behind their 541 homes, Shang warned them its “back-up generators would be noisy and pollute the air. And industrial-zoned land has no requirements to mitigate noise and pollution.

“The applicant’s 27 diesel generators will run during maintenance and emergencies, and when the data center needs more electricity from the grid. The decibel level then will be 63 dba, which is higher than allowed in our neighborhood. The noise will also affect wildlife and people working in the nearby office buildings.”

Pritchard returned to the Joint Land-Use Committee on June 19, saying they’d only have 20 generators; yet the county staff report lists 27. He said maintenance would be done in 30-minute increments, two hours/day, and “any leaking oil from the diesel generators would be caught and contained onsite.”

Virginia Run’s Jim Hart asked if large, semitrucks coming west on Route 50 would have to make a U-turn at Pleasant Valley Road to access the site. Pritchard initially said they would, so they could make a right turn into the site, but later said they’d have other options.

Another resident asked if Penzance would commit to using something other than diesel generators, but Pritchard said no. And when another person asked, “Will the applicant commit to any limits on electrical or water consumption?” Pritchard again answered no.

However, Cox said, “We can’t use so much water that there won’t be enough for your homes or fire emergencies. And there are no chemicals added to the water going into the data center.”

WFCCA’s John Litzenberger asked if power lines would be above or below ground, and Cox said, “Transmission lines will be underground, and Dominion would have to build us a new, electric substation. It’ll be a community substation for other commercial uses, as well.”

Pleasant Valley’s Ed Duggan asked, “Why don’t you build the substation yourself, instead of having the citizens, ultimately, pay for it?” But Cox only replied that Dominion said it must be offsite.

“Will you do periodic noise studies?” asked Sully District Council’s Jeff Parnes. Pritchard said they’d do them both before and after construction.

“What if there’s a brownout and there’s not enough power from the grid for you to run your generators?” asked SDC’s Jay Johnston. “Then you’d have to run your generators 12 hours/day.”

Replied Pritchard: “We don’t have an answer to that.”

“If the power goes out, you’ve got a backup – we don’t,” said Johnston. “You all are going to suck all the power out. A data center would use more water and power than a car dealership or warehouse would – so why would we want this?”

“The tax revenue to the county would be about $100 million,” said Pritchard. “A data center is a cash cow – a huge moneymaker. It’ll mean less money the county has to raise to do its work. And data centers don’t require services, such as schools.”

However, said Pleasant Valley’s Scott Gorvett, “A data center, with its noise and other adverse effects, could cause a $35,000 drop in my home’s value. And you’re taking this money away from all 541 homeowners.”

“It’ll grow the tax base, and I’m glad about the underground power lines,” said Litzenberger. “But if I lived in Pleasant Valley, I wouldn’t want it there. And I don’t think the applicant has adequately addressed the environmental issues.” The Land-Use Committee then deferred its recommendation until a later date.