Question juridique clé
Whether the appeal against the cantonal judgment was admissible and whether the Federal Court had grounds to intervene on the merits.
Solution extraite
The appeal could be heard only within the limits of the appellants' properly substantiated arguments; no ground for intervention was shown.
Motifs extraits
Challenges to factual findings on future noise were largely appellatory. The lower court could rely on Art. 15 USG and Art. 8 LSV without first definitively classifying the hall as a new or existing installation, because those provisions were the relevant environmental-law standards in the dispute.