IEEFA Urges FERC to Scrutinise Stale Environmental Data on MVP Southgate Pipeline

The Institute for Energy Economics and Financial Analysis has submitted comments to the US Federal Energy Regulatory Commission opposing a request by Mountain Valley Pipeline to extend the construction deadline for its Southgate Extension pipeline, arguing that the original environmental impact statement is now significantly outdated and that changed project conditions warrant fresh scrutiny. The current EIS was finalised in February 2020 — more than three years before the submission — and the requested extension to June 2026 would mean the document is more than six years old before the pipeline enters service.

FERC originally certified the MVP Southgate Extension — comprising approximately 73 miles of pipeline, a compressor station, and associated facilities connecting points in Virginia and North Carolina — on 18 June 2020. Since then, primary developer Equitrans Midstream disclosed in its first-quarter 2023 results that it is reconsidering the project's design, scope, and timing due to active negotiations with its shipper and a prospective customer. Design changes could affect both the project's costs and its environmental impact, and eminent domain proceedings in three North Carolina counties were voluntarily withdrawn in October 2022 — further signalling project instability.

IEEFA argues that the EIS must be updated to incorporate new research on methane leakage from natural gas pipelines. A peer-reviewed study cited in the submission finds that natural gas with a leakage rate as low as 0.2% is on par with coal for greenhouse gas impact over a 20-year period. A 2022 airborne basin-wide survey of New Mexico's Permian Basin found methane emissions 6.5 times higher than EPA model predictions, while a 2021 Stanford University study found methane emission rates 1.5 to 2 times higher than the EPA model and identified unintentional leaks as responsible for nearly half of all oil and gas sector methane emissions.

IEEFA also urges FERC to consider the impact of rising domestic natural gas prices driven by surging LNG export volumes, and to assess how the passage of the Inflation Reduction Act and the Bipartisan Infrastructure Law — which significantly improve the economics of renewable energy — affects the public interest calculus for the pipeline. The agency's own regulations require construction deadlines to guard against proposals becoming stale; IEEFA argues this standard has clearly been met here. The future of the mainline Mountain Valley Pipeline, on which the Southgate Extension depends, also remained uncertain at the time of submission due to pending legal challenges.

Key figure — 73 miles — length of the proposed MVP Southgate Extension pipeline, with its environmental impact statement already more than three years old at the time of the extension request