The Clinton-Gore administration disappointed some enviros yesterday as it made official for the first time its position on mountaintop-removal mining, a controversial technique used in West Virginia. A federal judge ruled last year that the mining technique, in which the tops of mountains are blasted off to get at coal deposits and the debris is dumped in valleys and streams, violates the Clean Water Act and a federal mining law. West Virginia is appealing that ruling, and the administration filed a brief in the appeal yesterday that appeared to support the continuation of the mining practice, while calling for some stronger environmental protections. Enviros had little time to review the brief yesterday, but some said it seemed the administration was attempting to allow mountaintop-removal mining to continue by weakening a Clean Water Act rule.