Question juridique clé
Whether the federal appeal against the cantonal judgment was admissible despite the decision being incidental.
Solution extraite
The cantonal judgment was an incidental decision under the Federal Supreme Court Act, and the appellants failed to show irreparable harm or that an immediate final decision would avoid extensive evidence-taking.
Motifs extraits
The remand left the noise-remediation issue open and could affect the closure question; prolonged proceedings and additional costs are insufficient irreparable harm.