Asarco, Inc. v. U. S. Environmental Protection Agency

The Environmental Protection Agency (EPA) appeals the district court’s finding that the EPA’s order requiring Asarco, Inc. to install a sampling station in the 1000 foot stack at Asarco’s copper smelter was arbitrary and capricious. The case requires us to consider the extent to which the district court may go outside the administrative record to review agency action. Although we find that the district court went too far in its consideration of evidence not in the administrative record, we find, based on our own review of the administrative record, that the EPA’s order was arbitrary and capricious, and remand the matter for further consideration by the agency.

Asarco is a copper producer that owns and operates a copper smelter in Hayden, Arizona. In 1974, Asarco constructed and commenced operation of a 1000 foot stack, which emits into the atmospheres gases and particulate matter that enter and mix in the stack from two separate flues or ducts. One flue carries gases and particulate matter from the Smelter’s roaster and reverberatory furnaces. The other carries gases and particulate matter from its converters. Asarco has sampling facilities on each flue to test emissions passing…