On Wednesday, the Fourth Circuit upheld the U.S. Army Corps of Engineers' decision to issue a CWA §404 fill permit to a surface mine in West Virginia. Environmental groups argued that the Corps made "a material factual error" and "misapprehended" the baseline conditions of the relevant watershed in its analysis of the cumulative impact. But the Corps considered the relevant factors, evaluating both the impact site and the entire watershed. Only after this evaluation did the Corps reach its informed judgment as to the baseline conditions. Nor was the Corps' finding of cumulative insignificance arbitrary or capricious.