Diesel generators—among the dirtiest and most polluting energy sources—were intended strictly for emergency backup use, not routine power generation. Yet the DEQ is proposing a rule change that would permit data centers to run thousands of these high-emission generators during planned outage events. Data centers in our region continue to seek permits for Tier 1 and Tier 2 diesel generators, which the EPA itself identifies as significant contributors to harmful air pollution. This proposal appears driven not by public health considerations, but by industry pressure to speed construction timelines and avoid investing in cleaner, though more expensive, alternatives such as Tier 4 generators.

The DEQ states that its mission is “to protect and enhance the environment of Virginia in order to promote the health and well-being of the Commonwealth's citizens, residents, and visitors.” Allowing widespread, planned operation of heavily polluting diesel generators directly conflicts with that mission. The DEQ does not currently evaluate or regulate the cumulative air-quality impacts posed by the rapidly growing number of diesel generators serving data centers in our area—impacts that will only worsen under this proposal.

As residents living on the edge of what Fairfax County now envisions as a major “digital gateway,” we strongly oppose this proposal and urge the DEQ to uphold its responsibility to safeguard our community’s health and environment.