On Nov. 3, 2025, Mountain Valley Pipeline (MVP), LLC, submitted an application for a Minor New Source Review (NSR) Permit to DEQ for its proposed MVP Boost project. MVP states that the purpose of the project is to provide expanded access to natural gas from the existing MVP Main Line project, which began operations on June 14, 2024.

In Virginia, the MVP Boost project would consist of the construction of the Swann Compressor Station adjacent to the existing MVP main line. The new compressor station would be a natural gas transmission facility, used to compress and transport natural gas through the interstate MVP main line, which currently extends from northwestern West Virginia to southern Virginia. 

Minor New Source Review (NSR) Permitting

DEQ’s Minor NSR Permit program applies to the construction of any new stationary source or any project that will emit regulated air pollutants above the exemption thresholds listed in 9VAC5-80-1105 C or D of state regulations, or that will require a permit via 9VAC5-80-1105 E or F. A source is considered ‘minor’ if it emits:

• Less than 100 tons per year of any criteria pollutant (particulate matter/PM, PM₁₀, PM_2.5, carbon monoxide/CO, nitrogen oxides/NO_x, sulfur dioxide/SO₂, and volatile organic compounds/VOC);
• Less than 10 tons/year of a single Hazardous Air Pollutants (HAPs); and
• Less than 25 tons/year of total HAPs.

Minor NSR permits issued by DEQ do not expire and remain in effect until the constructed facility or emissions unit is permanently shut down.

On Nov. 3, 2025, Mountain Valley Pipeline (MVP), LLC, applied to DEQ for a Minor NSR Permit for the Swann Compressor Station portion of the MVP Boost project. As proposed, the Swann Compressor Station would include:

• 3 natural gas-fired turbines for a total of 136,900 horsepower (hp), operating continuously (8,760 hours/year) for the compression and transmission of natural gas;
• 15 natural gas-fired microturbine generators potentially operating continuously to provide electrical power and backup power to the station;
• 5 natural-gas fuel heaters potentially operating continuously to preheat natural gas in order to maintain temperatures above dew point prior to combustion; and
• Additional equipment for cleaning and maintaining the pipeline (a pig launcher and receiver for pigging and blowdown of piping), as well as the installation of a mainline valve and auxiliary facilities.  

The application states that the proposed Swann Compressor Station would emit:

• 43.59 tons/year of particulate matter (PM)
• 44.36 tons/year of particulate matter 10 (PM₁₀)
  • Inhalable particles with diameters generally 10 micrometers and smaller
• 44.35 tons/year of particulate matter 2.5 (PM_2.5)
  •  Fine, inhalable particles with diameters generally 2.5 micrometers and smaller
• 22.72 tons/year of volatile organic compounds (VOC)
• 54.99 tons/year of nitric oxide (NO) 
• 46.57 tons/year of carbon monoxide (CO)
• 15.21 tons/year sulfur dioxide (SO₂)

According to the application, the proposed compressor station will not emit toxic pollutants above the state toxic exemption levels. Based on this information, the facility would be classified as a synthetic minor facility.

MVP’s permit application can be found under the ‘Project Documents’ drop-down tab on this webpage. DEQ’s Permitting Enhancement and Evaluation Platform (PEEP) can be used to track the status of this permit application, and to see what steps are next in the project’s permitting process.

• DEQ will hold a public comment period for at least 30 days (9VAC5-80-1170 D).
• DEQ will also hold an in-person public hearing. 
• After the public hearing has occurred and the public comment period has closed, the department will develop and publish a public comment summary and DEQ responses document.
• A second in-person public hearing will then be held, providing an opportunity for individuals who previously commented on the project during the public comment period (in writing and/or during the first public hearing) to respond to the public comment summary and DEQ responses document (9VAC5-80-45).    

• Publishing a notice in at least one newspaper of general circulation in the affected air quality control region,
• Uploading the notice to the Virginia Regulatory Town Hall website,
• Adding links to the notice on this DEQ webpage for the MVP-Boost / Swann Compressor Station project, and
• Including the public comment period and the first public hearing date on DEQ’s online calendar. 

State Surface Water Determination (SSWD)

The project applicant submitted a SSWD Request Form to DEQ in February 2026. The request seeks DEQ's determination of the absence or presence of surface water(s) under Virginia jurisdiction at the Swann Compressor Station project site (§ 62.1-44.3 of the Code of Virginia and 9VAC25-210-10 et seq.). Click on the files below to view the applicant’s SSWD submittal and DEQ’s response comments.  

• MVP's SSWD Request (received by DEQ on 2/11/2026):

MVP-Boost.Swann_Request for SSWD_2026-02-11

• DEQ's Comment Letter no. 1 for SSWD Request (issued by DEQ on 2/27/2026): 

MVP-Boost.Swann_SSWD – DEQ Comment Letter 1_2026-02-27

Isolated Wetland of Minimal Ecological Value (IWOMEV) Determination

The project applicant submitted a request for an IWOMEV determination to DEQ in February 2026. The request is specific to feature W-03 within the Swann Compressor Station project study area. After reviewing MVP's request and conducting a field inspection of feature W-03 on April 14, 2026, DEQ staff determined that W-03 does not meet hydric soils indicators. As a result, feature W-03 does not fall under DEQ's jurisdiction, and an IWOMEV waiver for W-03 is not necessary. 

• MVP's IWOMEV determination request (received by DEQ on 2/11/2026): 

MVP-Boost.Swann_Request for IWOMEV_2026-02-11

• DEQ's determination regarding feature W-03 (issued by DEQ via email on 4/14/2026):

MVP-Boost.Swann_DEQ email - No IWOMEV waiver required_2026-04-16

Federal Energy Regulatory Commission (FERC)

On Oct. 23, 2025, MVP submitted an abbreviated application to FERC for a Certificate of Public Convenience and Necessity to construct and operate the MVP Boost project. FERC issued a Notice of Application on Nov. 5, 2025, noting that a water quality certificate under Section 401 of the Clean Water Act may also be required for the project from the West Virginia Department of Environmental Protection (WVDEP).

Additionally, FERC had a scoping period from Nov. 19, 2025, through Dec. 19, 2025, during which input was gathered from the public and interested agencies regarding the MVP Boost project. DEQ provided a response to FERC's scoping request on Nov. 21, 2025.

With the scoping period closed, FERC issued a notice on Jan. 14, 2026, stating that it will prepare an Environmental Assessment (EA) for the proposed project, and that the EA would likely be issued in Aug. 2026.

Click on the files below to view these FERC-issued documents and DEQ's scoping response.

• FERC's Notice of Application (issued by FERC on 11/5/2025):

MVP-Boost.Swann_FERC - Not. of Application and Estab. Intervention Deadline_2025-11-05

• FERC's Notice of Scoping Period (issued by FERC on 11/18/2025):

MVP-Boost.Swann_FERC - Not. of Scoping Pd. Requesting Comments_2025-11-18

• DEQ's Response to Scoping Request (issued by DEQ on 11/21/2026):

MVP-Boost.Swann_DEQ - Response to Scoping Request_2025-11-21

• FERC's Notice of Schedule for Preparation of an EA (issued by FERC on 1/14/2026):

MVP-Boost.Swann_FERC - Not. of Schedule for Prep. of Environ. Assessment_2026-01-14

Montgomery County, Virginia

Many localities in Virginia administer a Virginia Erosion and Stormwater Management Program (VESMP) “for the effective control of soil erosion and sediment deposition and the management of the quality and quantity of runoff resulting from land-disturbing activities to prevent the unreasonable degradation of properties, stream channels, waters, and other natural resources” (9VAC25-875-20). Under a local VESMP, stormwater management plans, Construction General Permit (CGP) registration statements, permit modifications, etc., are submitted to the local VESMP authority where the land-disturbing activity occurs.

The proposed Swann Compressor Station would be located in Elliston, in Montgomery County. Montgomery County is a VESMP authority and regulates land development with the County as part of the municipality’s construction site stormwater runoff control requirements. The county is responsible for land disturbance permitting, as well as postconstruction stormwater facility inspection and maintenance requirements.

MVP's Minor New Source Review (NSR) Permit Application Submittal (received by DEQ on 11/3/2025):

• Application: 

 MVP-Boost.Swann_Application

• Environmental Justice Report:  

MVP-Boost.Swann_EJ Report with Appendices

• Modeling Protocol: 

MVP-Boost.Swann_Modeling Protocol

DEQ's Additional Information Request letter to MVP (issued by DEQ on 11/21/2025):

MVP-Boost.Swann_DEQ letter - Addtl. Info Needed_2025-11-21

DEQ's Review Comments on MVP's Swann Air Dispersion Modeling Protocol (issued by DEQ on 12/11/2025):

MVP-Boost.Swann_DEQ modeling protocol review_2025-12-11

MVP's Revised Air Dispersion Modeling Protocol for the Swann Compressor Station (received by DEQ on 2/2/2026):

MVP-Boost.Swann_Revised Modeling Protocol_2026-02-02

MVP's Local Governing Body Certification (LGBC) Form and Air Pollution Activity Suitability and Value (Site Suitability) Form (received by DEQ on 2/23/2026):

MVP-Boost.Swann_LGBC and Site Suitability Forms - Signed_2026-02-23

MVP's Control Efficiency Documentation (received by DEQ on 3/4/2026 & 3/6/2026):

MVP-Boost.Swann_Control Efficiency Documentation - emails_2026-03-04&06 

MVP-Boost.Swann_Control Efficiency Documentation - signed certification_2026-03-06

Updated Emission Calculations for Air Modeling

• DEQ's request to MVP for updated emissions calculations for air modeling (issued by DEQ on 3/17/2026):

MVP-Boost.Swann_DEQ - Request for updated emissions calcs_2026-03-17 

• MVP's updated emission calculations (submitted to DEQ on 3/23/2026 and 3/24/2026):

MVP-Boost.Swann_MVP - Revised emissions calcs - transmittal_2026-03-23

MVP-Boost.Swann_MVP - Revised emissions calcs - PDF_2026-03-23

MVP-Boost.Swann_MVP - Revised emissions calcs - transmittal_2026-03-24

MVP-Boost.Swann_MVP - Revised emissions calcs - spreadsheet_2026-03-24

• DEQ's review of MVP's updated emissions calculations and approval to proceed with air modeling (issued by DEQ on 3/27/2026):

MVP-Boost.Swann_DEQ - Review of updated emissions calcs_2026-03-27