FERC erred when it issued a 2018 certificate to Spire STL Pipeline LLC by failing to adequately examine the market need for the natural gas transmission project, an appeals court ruled Tuesday.

Spire STL pipeline

The U.S. Court of Appeals for the District of Columbia (DC) Circuit vacated Spire’s certificate and remanded it back to the Federal Energy Regulatory Commission. The court’s decision represents a win for the Environmental Defense Fund (EDF), which had urged the court to strike down Spire’s FERC certificate.

FERC should have more closely scrutinized Spire STL’s precedent agreement with affiliate Spire Missouri Inc., the EDF argued. The circuit court agreed.

“On the merits, we agree with EDF that the Commission’s refusal to seriously engage with nonfrivolous arguments...