Virginia DEQ fines Microsoft $2.5M over Leesburg data center
The Virginia Department of Environmental Quality (DEQ) has fined Microsoft approximately $2.5 million for exceeding fuel throughput and emissions limits at its Leesburg data center. This penalty, the largest civil fine ever assessed by the DEQ against a data center, resulted from a failure at an electrical substation that caused generators to run for seven days. Microsoft has since invested $31 million to install a dual-feed system to prevent future outages.
The Virginia Department of Environmental Quality (DEQ) has ordered Microsoft to pay a civil penalty of approximately $2.5 million for environmental violations at its data center in Leesburg, Virginia. This penalty is the largest civil fine the DEQ has ever assessed against a data center, according to a department spokesperson.
The violations stem from Microsoft's facility at 19515 Compass Creek Parkway exceeding its permitted fuel throughput and emissions limits. According to the DEQ's proposed consent order, the data center operated 62 generators for seven days during summer 2025 due to a failure at Northern Virginia Electric Cooperative's Cochran Mill electrical substation. The facility's permit allows for specific annual limits on diesel fuel consumption and emissions of nitrogen oxides, volatile organic compounds, and particulate matter, all of which were exceeded from October 2024 to October 2025. The DEQ issued a notice of violation to Microsoft on August 21, 2025.
Following the violation, Microsoft has invested around $31 million to implement a dual-feed electrical system at the data center, which is intended to significantly reduce the likelihood of similar extended outages in the future. A Microsoft executive signed the consent order on September 3, and it will be finalized after the DEQ accepts public comments through October 14. The penalty funds will be used by the DEQ to purchase air quality monitoring equipment for areas with high data center concentrations, with $1.5 million allocated for a mobile air monitoring station and $900,000 for 45 air quality sensors. Any remaining funds will go to the Virginia Environmental Emergency Response Fund.
A Microsoft spokesperson stated the company's commitment to responsible data center development and operation, confirming close collaboration with the Virginia DEQ during the event and supporting the expansion of air-quality monitoring in Northern Virginia.