Page-cited permit extraction

CyrusOne Northern Virginia Data Center - Maries Road

Loudoun Co., Virginia

QA status Machine-extractedRelease dated July 29, 2026

EVIDENCE NOTE

What the public record says

A machine-extracted candidate of equipment groups and permit limits stated in Virginia DEQ permit 74164-3, with one-based PDF page citations. Permitted terms do not establish actual operation or emissions.

Primary sourceVirginia DEQ permit document

Virginia Department of Environmental Quality

Open original source ↗

Summary fields cite p. 1 ↗, p. 3 ↗.

What this record does not establish

The source confirms the document and its stated fields. This profile does not infer actual emissions, compliance history, operating status, facility capacity or environmental impact where those facts are not established by the cited document.

How to read the status

Issued means the agency granted the permit subject to its conditions. It does not mean every permitted unit is operating, that maximum permitted emissions occur, or that later amendments do not exist.

MACHINE-EXTRACTED CANDIDATE

Equipment and limits,
kept separate from actual use.

These page-cited rows are machine-extracted and still require a second manual review. Verify every reused value against the linked official PDF. Page numbers refer to the one-based position in the linked PDF. Blank values are not zero.

Permitted equipment

4 document-defined equipment groups. Counts and per-unit ratings are transcribed; combined capacity is not calculated.

Reference	Equipment / model	Count / rating	Fuel / controls	Stated operating field	Source
`Group 2a 10-GEN-D1, 10-GEN-E1, 20-GEN-A1, 20-GEN-B1, 20-GEN-C1, 20-GEN-D1, 20-GEN-E1, 20-GEN-A2, 20-GEN-B2, 20-GEN-C2, 20-GEN-D2, & 20-GEN-E2`	emergency engine generator set—	12 units2500 kW each	diesel fuel oil—	See operating-scope table—	p. 5 ↗Machine-extracted from an official document equipment table; column grouping requires second review.
`Group 2 10-GEN-A1, 10-GEN-B1, 10-GEN-C1, & 10-GEN-R1`	emergency engine generator setMTU · 16V4000G84S	4 units2250 kW each	diesel fuel oil—	See operating-scope table—	p. 5 ↗Machine-extracted from an official document equipment table; column grouping requires second review.
`Group 1 10-GEN-A2, 10-GEN-B2, 10-GEN-C2 & 10-GEN-R2`	emergency engine generator setMTU · 16V4000G84S	4 units2250 kW each	diesel fuel oil—	See operating-scope table—	p. 5 ↗Machine-extracted from an official document equipment table; column grouping requires second review.
`Group HGEN HGEN-1`	emergency engine generator setCummins · DQGAF	1 units1500 or 1125 kW each	diesel fuel oil—	See operating-scope table—	p. 5 ↗Machine-extracted from an official document equipment table; column grouping requires second review.

Operating scope

Authorized hours, time windows or an explicit finding that no numeric annual-hour cap was located in the reviewed sections.

Limit	Basis	Source
500 hours/year	device in Condition 5. (9VAC5-80-1180) 11. Operating Hours - The operating hours of the emergency diesel engine gen-sets (Engine Groups 1, 2, 2a, and HGEN) are limited to the following: a. No single unit (Engine Groups 1, 2, 2a, and 3) shall operate more than 500 hours per year for all purposes (as provided in Condition 9), calculated monthly as the sum of each consecutive 12-month period; b. The emergency diesel engine gen-sets (Engine Groups 1 and HGEN) combined shall not operate: i. More thMachine-extracted normative operating-hours statement; second review pending.	p. 9 ↗
985 hours/year	re than 500 hours per year for all purposes (as provided in Condition 9), calculated monthly as the sum of each consecutive 12-month period; b. The emergency diesel engine gen-sets (Engine Groups 1 and HGEN) combined shall not operate: i. More than a total of 985 hours per year (combined), calculated monthly as the sum of each consecutive 12-month period; and ii. More than 100 hours per year (combined), for maintenance checks and readiness testing (that involves fuel combustion), calculated moMachine-extracted normative operating-hours statement; second review pending.	p. 9 ↗
100 hours/year	ecutive 12-month period; b. The emergency diesel engine gen-sets (Engine Groups 1 and HGEN) combined shall not operate: i. More than a total of 985 hours per year (combined), calculated monthly as the sum of each consecutive 12-month period; and ii. More than 100 hours per year (combined), for maintenance checks and readiness testing (that involves fuel combustion), calculated monthly as the sum of each consecutive 12-month period. This hourly limit does not include initial (one- time) commissMachine-extracted normative operating-hours statement; second review pending.	p. 9 ↗
150 hours/year	12-month period. This hourly limit does not include initial (one- time) commissions, unplanned maintenance, manufacturer recall updates, and repairs. c. The emergency diesel engine gen-sets (Engine Groups 2 and 2a) shall not operate: i. More than a total of 3,150 hours per year (Engine Groups 2 and 2a) (combined), calculated monthly as the sum of each consecutive 12-month period; ii. More than 320 hours per year (Engine Group 2) for maintenance checks and readiness testing (that involves fuelMachine-extracted normative operating-hours statement; second review pending.	p. 9 ↗
320 hours/year	and repairs. c. The emergency diesel engine gen-sets (Engine Groups 2 and 2a) shall not operate: i. More than a total of 3,150 hours per year (Engine Groups 2 and 2a) (combined), calculated monthly as the sum of each consecutive 12-month period; ii. More than 320 hours per year (Engine Group 2) for maintenance checks and readiness testing (that involves fuel combustion) combined, calculated monthly as the sum of each consecutive 12-month period. This hourly limit does not include initial (one-Machine-extracted normative operating-hours statement; second review pending.	p. 9 ↗

Permitted emission limits

33 pollutant, unit-group and limit rows. These are permit terms, not measured or actual emissions.

Inspect 33 transcribed limit rows

Reference	Pollutant	Limit	Basis / scope	Source
`Engine Groups 1 and 2`	NOx as NO2—	44.31 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	NOx as NO2—	48.06 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	NOx as NO2—	20.52 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and 2`	NOx as NO2—	9.37 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	NOx as NO2—	7.05 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	NOx as NO2—	5.73 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and 2`	VOC—	2.20 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	VOC—	1.10 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	VOC—	0.95 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and 2`	PM10—	0.78 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	PM10—	0.56 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	PM10—	0.48 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and 2`	PM2.5—	0.78 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	PM2.5—	0.56 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Group 2a`	PM2.5—	0.48 lb/hrhourly	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and HGEN`	NOx as NO2—	21.82 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 2 and 2a`	NOx as NO2—	75.69 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1, 2, 2a, and HGEN`	NOx as NO2—	97.51 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and HGEN`	NOx as NO2—	4.61 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 2 and 2a`	NOx as NO2—	14.76 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1, 2, 2a, and HGEN`	NOx as NO2—	19.37 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and HGEN`	VOC—	1.08 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 2 and 2a`	VOC—	3.47 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1, 2, 2a, and HGEN`	VOC—	4.55 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and HGEN`	PM10—	0.38 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 2 and 2a`	PM10—	1.23 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1, 2, 2a, and HGEN`	PM10—	1.61 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1 and HGEN`	PM2.5—	0.38 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 2 and 2a`	PM2.5—	1.23 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
`Engine Groups 1, 2, 2a, and HGEN`	PM2.5—	1.61 tpyannual	——	p. 11 ↗Machine-extracted from an official permit limit table; header grouping requires second review.
	visible emissions—	5 percent opacityvisible	——	p. 12 ↗Machine-extracted from a page line in an older official PDF; literal context: Page 10 16. Visible Emission Limit - Visible emissions from each emergency diesel engine gen-set (Engine Groups 1, 2, 2a, and 3) exhausts shall not exceed 5% opacity except during one 6- minute period in any one hour in which visible emissions shall not exceed 10% opacity as
	visible emissions—	10 percent opacityvisible	——	p. 12 ↗Machine-extracted from a page line in an older official PDF; literal context: 16. Visible Emission Limit - Visible emissions from each emergency diesel engine gen-set (Engine Groups 1, 2, 2a, and 3) exhausts shall not exceed 5% opacity except during one 6- minute period in any one hour in which visible emissions shall not exceed 10% opacity as determined by EPA Method 9 (reference 40 CFR 60, Appendix A). This condition applies
	visible emissions—	20 percent opacityvisible	——	p. 12 ↗Machine-extracted from a page line in an older official PDF; literal context: During startup and shutdown, visible emissions from each emergency diesel engine gen-set shall not exceed 10% opacity except during one 6-minute period in any one hour in which visible emissions shall not exceed 20% opacity as determined by EPA Method 9 (reference 40 CFR 60, Appendix A).

DOCUMENT HISTORY

What this document says it changes

amended or superseding permit document

Explicitly supersedes the document dated 2020-02-21.

p. 1 ↗, p. 3 ↗

QA NOTES

Ambiguity stays visible

Machine-extracted candidate. Verify every reused value against the cited official PDF page.
Verify table column grouping and any alternative models.
Confirm whether the limit is per unit, combined, or limited to testing/maintenance.
Confirm multi-row and merged-column header association.
Older-PDF text fallback; verify row and unit alignment.

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