Microsoft Leesburg (IAD01-02-03-04-05) Data Center, Leesburg
approved CampusOperated by Microsoft Corporation
Virginia DEQ issued Microsoft an amended air permit (Registration No. 74220) on March 7, 2025 covering emergency engine gen-sets and three diesel fire pumps at the Leesburg IAD01 through IAD05 data center. The permit equipment list covers 100 Caterpillar C175-16 emergency gen-sets rated 3,100 ekW each, permitted in tranches originally dated June 26, 2020, December 21, 2021, September 14, 2023, and August 16, 2024, plus two Caterpillar C27 units at 750 ekW and two Caterpillar C32 units at 1,000 ekW.
Land use jurisdiction: Town of Leesburg
Measurements on record
Permitting path
Approvals on record for 1 of 11 path steps; latest: DEQ air permit (generators) (2025-03-07).
Virginia's sequence runs through county land-use case records to DEQ air permits; rezonings and special use permits are the public record spine, and DEQ publishes the data-center air permit register.
| Date | Step | Authority | Instrument | Status |
|---|---|---|---|---|
| 2025-03-07 | DEQ air permit (generators) | Virginia Department of Environmental Quality | Article 6 minor NSR permit (amended), Registration No. 74220
Article 6 minor NSR permit (amended), Registration No. 74220 (original) |
on record |
| Site control (deed or lease) | not yet requested | |||
| Special use permit / site plan | Town of Leesburg | not yet requested | ||
| Rezoning applies where the site's zoning does not already allow the use |
Town of Leesburg | not yet requested | ||
| Natural gas service applies where the facility uses natural gas |
not yet requested | |||
| Utility interconnection (PJM queue) | not yet requested | |||
| Sewer service commitment | Town of Leesburg (sewer service) (municipal limits) | not yet requested | ||
| Water service commitment | not yet requested | |||
| Building permit | Town of Leesburg | not yet requested | ||
| Stormwater (VSMP permit) applies where land disturbance passes permit thresholds |
Virginia Department of Environmental Quality | not yet requested | ||
| Public agreements and incentives applies where negotiated with the host jurisdiction |
Town of Leesburg | not yet requested | ||
| Go-live | not yet live |
Steps without a record are shown as not yet requested or not on record: absence of a record here is a records gap, not a finding about the facility. An authority shown for an empty step is the body that would issue it. Some authorities are shown before any record exists, from mapped utility service areas or, for sewer service, from municipal limits; these carry a marker naming the basis.
Site control comes first in every path: a proponent must hold a deed, lease, or purchase option on every parcel of the site before it can apply. Parcel and ownership records have not yet been pulled for this facility.
About this path and the law behind each step: the law on record for this jurisdiction
Location and sources
Leesburg, Loudoun County, Virginia
Every record links to its source: public records, press reporting, and openly licensed datasets including Epoch AI, Wikidata, and US EPA. Full sourcing and per-source licensing: methodology · sources.