The denial was one of many made in one-line orders without comment.
The Hill newspaper said the high court denied a request from a major copper company, Asarco LLC, to review an appeals court decision upholding the EPA's 2010 air pollution regulation. The newspaper said the rule has evoked challenges from several states as well.
Asarco operates a large copper smelter in Arizona and said the EPA rule will force industries to incur "enormous expense." The Hill reported.